I see a lot of talk about kickoffs and how bad coverage is which is why everyone seems to kick to the FB. I can tell you I never kick to the FB and so far this year I've have maybe 2 people return for TDs out of all the games I've played which at this point is probably a couple of hundred H2H. I always consider how I fill backup spots in my team and wanted to share so all of you know which backups will actually see the field and which can truly just be for chem purposes so you can make better choices.
Bench Warmers
First, let's start with the positions that will never see the field unless you manually sub them in.
These are LT2, LG2, C2, RG2, RT2, HB3, QB2, MLB3, MLB4, CB5, LE2, RE2, DT4. All of these positions can be filled with gold cards who get your team chem or the cheapest cards you need for legends chem. These will hardly ever see the field and may have to be manually subbed in no matter what Offense or Defense you play. The exceptions are on field goals you will probably see RG2 and QB2 on Field Goals and LE2 some special teams defensive formations.
Special Teams
Now, the positions you need to consider getting solid backups for because they will see the field per the special teams chart which should be accurate below:
What I look for for these backup positions is Speed and Hit Power. Other stats don't matter as much except maybe BSH but you mainly want speed. All of my backups have 85+ speed to get to the return as fast as possible and ensure they don't even make it back to the 25 often. I'd rather kickoff to their returner and stop them at or before the 20 than kickoff to the FB and have them start at the 30 consistently, that extra 10 yards is an extra set of plays they have to run where more mistakes are more likely to go in my favor.
To see all my backups check out my lineup and you'll see the key ones mentioned for special teams per the image above are all solid OVR to ensure I have adequate kick coverage - Sevein131's Mut23 Lineup
Obviously, if you have to run a theme team and can't lose any team chems, you are going to want the best player your team at every position contributing to chems, but if you don't have that concern, you want the fastest players at each of these key backup positions for kickoff coverage.
Scheme Players
Other things to consider is which backups are scheme dependent based on what you run.
Offense
Example, if you run heavy sets that utilize all 3 TEs like I do, you will want to ensure TE3 is a beast of a card that fits your scheme whether it is speed, route running or run blocking. If you only run 1 or 2 TE sets, then you may not need strong players at those positions and can get the cheapest players that fit your chem needs.
Same goes for number of receivers, focus on the number of receivers you usually have in the field to determine how many goons you need, i.e. 2, 3, 4 or on the rare occasion, 5 receiver sets will determine how many players you need to fit your scheme and how many can just be chem fillers who will never see the field.
You only ever need 2 HBs and as long as you are balanced in run and pass it is unlikely you'll need to sub them in or out for one another, if you are running every play no matter what, you will want to keep an eye on stamina and sub in accordingly on the play selection screen or just get in the habit of alternating subs each down so you don't have to watch stamina too much. Either way, never go into a game with only 1 HB because these are the workhorses of the field who need a break here and there to limit fumbles.
Defense
If you run Big Nickel Over G (BNOG for short), you are going to want a strong SS2 because you will be able to have SS1, SS2 and your two sublbs 1/2 on the field all at once. Another tip if you run this D is to ensure all 4 players are different, i.e. do not have either of your sublbs on the specialist screen be the same as either of the players you have at SS1/2 because all 4 will see the field and if you have a dupe player for any, the game will put your next highest rated player in for you and you might not like who it selects.
If you are a heavy Dime user, your CB4 probably comes into play often, same with 46 Normal Speed package, it will place your CB4 in the box as a sub lb alongside your MLB1.
Prevent Defense brings in your CB4 and FS2, you shouldn't be in this defense often but something to consider if you find yourself need it.
Goal Line Defense, which is obviously situational as well should bring in your DT3, so you want a big boy to fill that hole if you can, otherwise you'll have to rely on who you are using for chems in that spot or manually sub another player in the spot.
As always, do remember you can sub players in too for key moments so if you have a weak FS2 for chem purposes but you have a strong CB5 who never sees the field and call prevent, you may consider subbing in FS2 with that CB5 or that specific game and formation. This information is more for reference so you know when you may need to make these types of decisions depending on your backups.
Conclusion
Hopefully this all helps brings a little clarity to what backups are important and which can truly be just fillers so you can focus your personnel moves accordingly.
If there is anything I missed or anything you consider for backups or special teams, feel free to share below!