Bounded accuracy includes having smaller defenses. Most monsters target armor class. Adding proficiency on top of that stat... completely negates all the work put into the game to make bounded accuracy work. It would make the DM work harder, creating orcs at various levels that are a threat...
By game, I mean campaign... as in mixed company. One min-maxxer just ruins it for everyone else. I've seen way too many games ruined because the DM is incapable of telling the min-maxxer to stop just to keep the game going.
1st level dips are horrible because they make some classes way more powerful for cherry picking than others. It is ripe for abuse by min-maxxers, who should never be allowed to ruin a game.
I like the multi-class ability score requirements.
I like proficiency bonus. It's basically the D&D Next version of the half-level bonus in D&D 4e, but toned down.
To 1of3, go dex/wis for archery via Ranger multi-class.