Here's mine:
QB: Luke Doty
RB: Kevin Harris (can he build Heisman momentum?)
TE: Nick Muse
TE: EJ Jenkins (portal from St. Francis; could they roll him to WR?)
WR: Jalen Brooks
WR: Josh Vann or OrTre Smith (now or never, dudes)
WR: Xavier Legette
OC: Eric Douglas
LG: Jaylen Nichols
LT: Jazston Turnetine
RG: Jovaughn Gwyn
RT: Dylan Wonnum
Very similar to my choices:
QB: Doty (he is miles above everyone else at the position in terms of game experience, even if it's not great in itself)
RB: Harris (he earned this right - Lloyd needs time to slowly work his way into college FB and recovering from his injury, and White is still proving himself, but both as well as Rashad Amos will get carries and make up great depth)
TE1: Muse (after Shi Smith, Muse was easily the #2 receiver last season, and Smith is gone. So like Harris, he's a de facto starter.)
TE2: A lot of good options here: I put Keveon Mullins first - he's a WR convert to TE who missed half of last season with an injury, but had some good plays including the offense's longest reception of the season in 57 yds from Hill. Also had another for 44 yds - he only had 3 receptions all season, so he seems built as a big-play receiver! He's also the most senior Gamecock of the rest of the suspects as a red-shirt sophomore. After him, Jenkins is a good choice, but also I expect Traeveon Kenion, Jaheim Bell, and Eric Shaw to be in solid position. None of them did anything last season, and its a whole new staff, but they were all high 3-star/low 4-star prospects who will be sophomores with a year in a college program, so they should be ready to start contributing)
WR1: Vann and/or OrTre are both seniors, and as you say it's now or never for them. Vann hasn't shown anything in his career, but Smith has, although it's been ages ago. 6-7 Transfer Jenkins will add his length to 6-4 Smith and 6-5 Ger-Cari Caldwell as our tallest targets.
WR2: Jalen Brooks and/or Ahmarean Brown (Wingate transfer Brooks struggled to make the field in games last season and only played in 6 games, but he had more receptions for more yards, and at a greater average than Vann who appeared in all 10 games. It could be his time to break out. Georgia Tech transfer Brown is not as tall as Brooks, but like Brooks he led his former team in receiving and it was a P5 major program as well, so he may be on a faster track to contribute. Brown is also perhaps immediately the speediest WR on the team, and will be a good option to replace the departed Smith in that capacity.
WR3: Legette (like Brooks Legette only appeared in 6 games last season, but was 3rd behind Shi Smith and Muse for non-running back receivers in total receiving yds with 118 yds. Also former 4-star Rico Powers will get runs here.
The OL is perhaps the most solid position, with 4 of 5 starters returning from last season, losing only Sadarius Hutcherson at LG.
C: Eric Douglas (A senior, Douglas started all 10 gms last season at Center, and has a total of 11 starts in his career. I imagine Hank Manos will back him up)
LG: Jordan Rhodes (rs-senior who started 10 games at LG in 2019 when Hutcherson was moved that season to LT. He missed fall camp practice time choosing to opt out due to covid-19 but then recanted and returned to the team. He only played in 4 games last season, and spent time with the OL. Expect to see some snaps go to Tyshon Wannamaker)
LT: Jakai Moore (this position was up for grabs for most of the season until Moore took over. Dylan Wonnum started the first 3 games there while Moore started at RT for the 1st 2 gms, then the 3rd game vs Vanderbilt Vershon Lee started at RT while Moore backed him up. Then Wonnum moved back to RT for the final 7 games, and JUCO OL Jazston Turnetine started at LT for the next 3 gms. FINALLY, Moore started at LT for the final 4 gms of the season, to give him a total of 6 starts at both tackle spots over the season, and a total of 8 starts for his career. Whew! I expect Moore to continue to start at LT, with Turnetine available to back him up effectively.
RG: Jovaughn Gwyn (total 21 starts - all consecutively at RG - and 23 total gms. He is part of what will be a rock steady right side of the line for USC. Vince Murphy and Wannamaker will provide supporting depth)
RT: Dylan Wonnum (total 24 starts in 26 gms - Wonnum was moved to either side of the line at Tackle, but his consistency has been at RT. Jaylen Nichols, who has 4 starts at RT in 2019, and Vershon Lee will back him up there).