You are correct, to get his fitness up he needs to play matches. However, he apparently has no cartiledge on the knee and that could be an issue later in the season. Nic Nat was amazing on Sunday, running and tackling, didnt expect he would move so well.
Unfortunately every ruckman has his issue. Stef is an older player and mid season his body gets sore, that is why Archie played six games last year, to take some of the load off Stef. May not happen this year, just a factor.
I have an underperforming Lycett and will be hoping he pulls his head in and play properly and stop giving away free kicks. He will be doing this whilst sitting on my bench and I give English a crack at R2. Agree Witts and tackling machines like Holman likely benefitted from plenty of stoppages.
The only point I would put less weight on is the bye, if you get a good ruckman this year, just back him in. The ruck situation is too hard this year to be putting too many constraints around it.