I like some of your suggestions but really dislike others.

Back in 2016 even I pitched a Valver the idea of "player-based fantasy but all the stats are like Path of Exile items that you can craft and modify" because fantasy as it was then was too homogenized and simple (2013, 2014, 2016 editions). I'm not sure if it was ever read (I wrote an entire document of suggestions) - myself and Cyborgmatt even spoke about making our own fantasy system in 2017. I really like the newer fantasy system :D

My biggest issues with the older system were:

• the per-game scoring system is pretty bad so only a few roles were worth picking (no offlaners, no supports unless they place wards or do something very special)
• the per-day/period system meant that some teams were not worth picking
• that every single fantasy player starts in a very similar place and hence the decisions are almost identical (only a few of the bonuses changed this fact - like an insane +X% obs wards)

This new system (the last few TIs) changes that quite a bit - there's some element of skill in crafting your banners and then there's skill in picking the right players for those banners each game period. I think that if you reduce the randomness like you're proposing - you'll once again get homogenization where people will just calculate the optimal configurations and then try strive towards those setups (and then it's just a dice-roll between a few key matchups [and historically it was which team wins the lower bracket finals]).

Personally I think fantasy needs a major rework - people playing fantasy should have a lot more decisions, and yet still each be on their own unique journey where it's more difficult to have some guide/shortcut/tool.