I do not think Erlbeck will be in the running.
The Birtwistle vs Thomson argument is an interesting one. Personally I think they need a player who compliments both Hiltz and Spallina. I think Thomson is a bit too similar to both players, and it seems to me he sees the field a bit better from above GLE than behind it. He's a really good player and this is not meant to take anything away from him, but I think he's better served in the midfield. I wouldn't be upset at all if he was given the attack spot, but that's my opinion.
With Birtwistle you'd get a proven finisher who is able to finish in close and also has range. This is a move that I could definitely be in favor of as he's really talented and I don't think he got enough playing time this year. I still would prefer a pure dodger to take some heat off of Spallina, but he's shown the ability to do it on occasion. Plus he would add some size to the unit which is a bit undersized. He finished the 2022 season on attack and of course played very well there. Given that they didn't really play him there at all this season I don't think it's likely he plays attack there but you never know.
One other option is to figure out how to fit Trey Deere onto the unit, probably using him as a crease attackman. I think he'd be pretty similar to Birtwistle but with more passing ability. Given he's a lefty not sure how well it would work, but Duke has figured out how to play two lefties together in Brennan O'Neil and Dyson Williams.