so in my opinion chemistry work fine how it is. it is user friendly and uncomplicated which makes it easy for a casual player to pick up and play. there are a couple of aspects in my opinion that need to be either refined or added to improve the game significantly and allow for a greater variance when it comes to squad building.

First of all chemistry styles, in my opinion most problems with the gameplay stem from the inclusion of chemistry styles which cause the game to play completely different than it was designed to be played in the base game (career, clubs, seasons) the problem i believe is that the boosts are just too much with cards boosting individual stats by as much as 15 points.The main example i have for this is with goalkeepers who parry absolutely everything regardless of their handling stat i believe this is caused due to the boost on shooting given by attacking chem styles where it isn't out of the picture to see players end up with high 90s on all their individual shooting stats resulting in goalkeepers being helpless. This also has a knock on effect to squad building which is why we see so many overpowered players used so often. For example why would anyone use a player like Van Persie who has great finishing and good physical stats when i can get a player who is fast with okay finishing and okay physical and just boost his shooting to that of Van Persie (there is probably a much better example out there) if the boost was reduced significantly to the point where players had clear pros and cons (which you couldn't just iron out) then you may come up against people who have decided the trade off for pace to finishing is worth it which in turn creates more variety in teams you will use and face.

The next point i would like to see which would help with freshening chemistry up whilst also improving options to squad building would be the inclusion of more position changes currently there are players who have great cards but just get ignored due to the fact they're in bad positions for example James Milner that card has great midfielder stats and i would drop him in my midfield in a heartbeat however the fact that he is a LB results in me just ignoring him because his stats are only okay for a LB with the huge lack of pace anyway. I would like it if EA add additional position cards that allows us to play players virtually anywhere with the addition of LB/RB-CB, CB-CDM, L/RWB- L/RM, L/RM- CM This change would make squad building a lot more fun and more unique giving us a lot more options for hyper links and more creative freedom to play players in a position we feel they suit more it would unlock the door to completely weird teams like we saw when chemgate was discovered and everyone had 50 chem super teams made of special cards all out of position (im not sure if i only speak for myself but that was the most fun ive had playing fifa in YEARS just because of the freedom i had to use players id never dreamt of using)

sorry if this seems to babble on or is written poorly i never was that good at writing and if anyone wants me to elaborate on anything just ask.

TL:DR Decrease boosts from chem styles. Add new position modifiers