I've probably only seriously considered four starting picks in the rucks to this point:
English - because he's still coming into his prime years for a ruck and has shown that when he's on, he can rack up 20+ disposals and a bunch of marks playing on the ball as well as rucking. 5 games at 120+ to start last year showed us what he is capable of: he's the one I most fear getting 150s when he's not in the team.
Marshall - because if he gets a full year as a solo ruck he has shown he can go 110, so he's cheap for that kind of output.
Grundy - to be honest, I don't think he's been quite the same after that neck injury in 2021. He's still clearly a capable footballer and far less use as a back or a forward than Gawn (he's also 3 years younger), so surely he gets a good chunk of ruck time with an awesome midfield at his feet? Getting to 105 is probably enough for an R2 that doesn't break the bank.
Cameron - because he's really a forward that you can start in the ruck line so the pass mark is lower. Has shown 100+ scoring as a solo ruck so it's there, just a question of whether he can pull out a good chunk of the season doing it.
The rest? Not for me.
Unless there's a playing rookie ruck in Round 1, in which case I'll probably pick him. I always do