what are the most important positions on offense and defense like in order

how would you order them?

Offense: QB, WR1, RB1

DEF: User(usually SS in sublb1) , Cb1, Cb2 

The others are also important but you can get by but if you dont good cards at those positions you will not have a good time.

offense: qb, OT , wr, te, rb IOL
defense: user, cbs, edge rushers, S, DL, LBs

Offense- QB, RB, WR1, WR2, TE, WR3, LT, C, LG, RT, FB, RG

Defense- CB1, MLB1, CB2, SS, FS, RE, LE, LOLB, ROLB, MLB2, DT1, CB3, DT2

O: QB > RB > WR1 > WR2, TE> LINE > WR  3, FB

D: USER> SS > CB1 > FS > CB2 > OLBS > D LINE > CB3 > MLB

I might argue that TE1 and 2 are just as important as WR1 and 2.....I run a lot of 2 TE sets, sometimes 3 TE....Metzelaars, Delanie, and soon to be Pitts. HUGE difference in the run game and also, those 3 can catch, and can truck guys after the catch. All are mis-matches for safeties and especially LBs.

Plus if they stay in to block, much more effective than WRs (other than Hines Ward)

On D, right after your user, I think your edge rushers are probably next. Leonard Floyd, with Double or nothing and edge threat, along with Seymour with defensive rally for 0 AP, is an absolute problem for any offense. With Strahan or another really solid pass rusher on the other side, with under pressure...the opposing QB  either won't have time to throw to a developing route, or will get an accuracy penalty for being under pressure unless he has fearless (and then he only has immunity to pressure with set feet in the pocket - that's how fearless is supposed to work).