I totally get the desire to go classless - but it annoys me when people go halfway with it. Most of 5e's weaknesses come from an unwillingness to commit to being one thing or another, so they split the difference and end up will all the downsides and only a few of the upsides of the two things they dithered between. For example, the weapons list is to vague to make the choice of weapon mechanically meaningful, but to specific to let you just take whatever weapon looks the coolest.
So go all in: make it classless and add talent trees alongside feats to cover features that should be linked (like, say spellcasting).