I've played a good 20+ years of active Champions and Hero system play in the past 40 years (same with GURPS, which draws a lot of comparisons). Here are my thoughts (usually in form of explanation & value, then potential downside):
It is a 3d6 resolution game. This has the advantage of making the minor changes in your score level being checked actually matter (to diminishing return, as moving a check from 10- to 12- is massive, but 15- to 17- less so). The only real downsides I see are 1) by having the change in effectiveness all on the dice curve and have the cost of scores be linear, at moderately high point games (or if you place enough situation-limiters) you can have effectively-can’t-fail checks (which can mess with gameplay assumptions in the rest of the system). 2) There are a huge number of tables with modifiers (small and large) which, depending on if the DM decides to use them (and whether, say, they even had an idea about what the light level or wing speed was before the table reminded them that it matters) can readily drown out the effort someone put into raising such and such a skill value.
It is a trad game with lots of focus on how well you can pick up, push over, move about, deal damage, what you can see, etc.; but with a lot of the needling details abstracted or shoved to the corner (in theory there is encumbrance, but in a game where gear-tracking and loot are not default assumptions, it shoves them off the corner; wealth is abstracted to bands in the default as well). It also has a general (non-combat and sensory) skill system that allows you to do social and professional skills, etc. (although exactly what you can do with, say, a psychology skill is going to be incredibly vague unless you have a supplement that deals with it). There’s nothing wrong with this unless it isn’t what you were looking for.
More broadly, it focuses on the genre-immersion level of verisimilitude, rather than quasi-realism. Exactly how is hard to pin down, excepting what I mentioned above, and perhaps that more (compared to GURPS) specific rules tend to be built of general ones, rather than having specific ones in place for real-world scenarios (example: bleeding wounds can happen in either, but GURPS has specific bleed-out rules, while with HERO is would be built out of points and function just like any other ongoing-damage effect; therefore it is easier to jettison them if that’s not the kind of combat power fantasy you are seeking).
It is generic, and (better than GURPS) does a good job of scaling up to the power scales that most genres deal with (Supers and space opera being notable examples). At the same time, it works well (if perhaps not as ‘realistically’ as GURPS) at lower power level/gritty scales.
It defaults to not-horribly-lethal, which I think is the optimal choice for a game where character creation is time-consuming and player-character investment is high.
It’s complex, but a lot of that is in the character creation (unless you have abilities with wide-open effects, which have lots of warning signs around them), and around the massive tables of modifiers. You can of course ignore both of those most of the time. However, those seem to also be a lot of the appeal of the game (I think nearly everyone who has played Hero/Champion or GURPS has multiple spiral notebooks full of characters or equipment or whatnot that they built using the build-from-points system that they never expect to play), so if you aren’t engaging in the complexity, you find it hard to sell your group on the system.
The system, in general, is pretty solid. Resolution is relatively quick (minus decision paralysis or people having trouble tracking a handful of often-changing values like two HP tracks plus Endurance and duration of ongoing effects). Like many games, characters have to-hits vs enemy to-not-be-hits and then if a hit occurs damage, minus damage-resistance is subtracted from Body and/or Stun. There are multiple brands of defense-offense scores (physical and mental), as well as several damage types/resistances. This can be an avenue for creativity, although it can also seem like you’re just going ‘okay, the enemy is strong vs our red-effects, anyone have anything resisted by orange?’ There’s also the scenario where you had no idea someone would build sonic attacks resisted by sound-base Flash-defense and that fine line between being creative and cheezy. Like any ‘build’ system, there’s some level of ‘the best way to have beaten the last challenge more easily would have been to have levelled your character different last time you got more points’ which may of may not speak to some people.
And, of course, it is a point-buy (generic) system. Point-buy generic systems run into a fundamental issue that a given quality isn’t ‘worth’ the same amount in all contexts and at all power scales and in all possible settings (and with other buyable options or gameplay systems turned on or off). Mind you, both Hero/Champions and GURPS don’t actually say that they are a balancing mechanism, but plenty of components within them tacitly do (such as: you are awarded points based on how well you do in adventures, the cost of ally groups depends on how many points they have, etc.), people will use them that way regardless, and most other alternate explanations for what they are fall into the ‘okay, but an actual balancing system would be more useful to me’ camp. Nearly every time someone mentions this, someone will say that they are a Fairness mechanism rather than a balancing mechanism, which, okay how does that help (what it seems to do is make people hypervigilant to someone else getting through story consequence what they paid points for, which yeah it does suck if you paid for a fancy rifle and the guy across the table took one off a knocked-out guard, but that’s also maybe part of a fun adventure). Even holding that aside, some of the costs seem arbitrary or sometimes strange, with things like Life Support (not needing food, water, air, or specific temperature) being incredibly cheap compared to any kind of combat benefit (in games that clearly do focus on combat, regardless of how universal they are). You can get more points by taking on disadvantages, which has obvious benefits (weighing options, bad things can happen to you and you really shouldn’t feel singled out since you chose them, etc.); but also have some negatives --GM has to remember to invoke many of them, many supposed disadvantages are really guaranteed spotlight time, for the rest the optimal choice is to choose disadvantages you don’t think will come up (thus least interesting), etc.
Fundamentally, I like the game and have fond associations with it. Also, I don’t think there’s really anything categorically wrong with the game (I have similar positive associations with WEG Star Wars, but recognize its scaling-problem as hard to ignore). I think it’s time with my main gaming groups are probably in the past, though. No one really has a passion for the bean-counting of character creation any more – even though, yes, (1+(1/4+1/2+3/4+5/4))/(1+(3/4+1/2)) isn’t actually complex (it just feels meaningless). Likewise we’d rather use disadvantage systems which reward leaning into the flaws, not trying to avoid them. Still, my overall opinion of it is positive. To what others have said, if you aren’t going to play the game, I find the GURPS supplements a better read-through. Make of that what you will.
