Personal opinion on auto subs is use 20 between each. So for me personally, I believe it should be like this.
Qb 45 out 65 in
Rb 60 out 80 in
wr 55 out 75 in
TE/FB 50 out 70 in
OL 40 out 60 in
I feel as though when you go over 80 your players dont come back in enough at the end of the game. I also run aggressive Clock adjustment on offense unless its late and I need to run the clock. This allows players to sub in more frequently. I have ol at 40 and 60 because they never sub in real life unless injured. You could switch it with the qb if you dont have a backup you ever want to see the field, but option teams bring in a backup here and there at qb.
Defense is the same principle, the game came with a 20 point difference for a reason, thats how the game was made to be played. you could also use random numbers instead of multples of 5, I like everything to look clean/official.
60 80 dt
55 75 de
50 70 lb
45 65 cb
40 60 S
If you're willing to see big names be out on big plays, or you're a powerhouse with incredible depth, you can go higher than 80 for sub in but I wouldnt advise it. You can go lower than 40 out if you really just never want to see a position sub. I feel as though this does a good job though. If there's someone you specifically want to get touches that dont seem to be getting them, use formation subs to make them the starter in some.