You'd be hard pressed to find someone that hates o5e as much as I do, and I'm excited for Level Up. Martials get plenty of fun options and aren't stuck saying "I hit it X times" and then waiting while all the Mages make interesting dynamic choices. Doubtful Wizard will still be the best Martial in the game. Spells are actually balanced and "iconic" ones weren't intentionally OP to 'encourage' people to take them. With Exploration and an Economy among other stuff it's a complete game that doesn't ask the DM to play on-the-fly Game Designer. There's actual Math behind monsters and encounter design. Choices after Level 3 for non-casters. The main things I'm concerned about are the dice rolls involved in generating ability scores and HP at leveling up, but that's a backwards compatibility thing. Adept should hopefully get more out of Archetypes than things strictly inferior to Stunning Strike. I think Skills are going to be able to do more so hopefully will be less bogged down by the faulty assumption that like Martials they need to feel realistically mundane as opposed to Magic which can do anything "Because Magic". Basically, everything they have shown has only increased my faith in them in spite of the system they are building off of.
