I think Twal is a bad option at lock, I'd only play him at prop.
In defense, he's a solid defender front on, but isn't that effective when he needs a bit of lateral movement and his line speed is not that great.
In attack, he's very limited with one out hit ups and absolutely no passing. Props who have played that role well have either been dynamic attacking players or players with good ball skills.
I think the strategy is to toughen our defense with him there, but like I said, I don't think he's much of a difference maker.
My preference is to run a rotation of bird and fainu, with fainu coming on at the end of the half to hopefully add some speed and attacking threat. Both have good line speed and can play the disruptor role to the other team and both are strong tacklers. Both also have passing and creativity, where whenever Twal gets the ball in the opposition 20 you know nothing is going to happen.
I'd run with da silva, pole, hunt and fainu on the bench. I know that's a little light, but I think rotating the hookers is important and bird, seyfarth, doueihi, fainu all have versatility and I just think we're far too one dimensional in attack and our defense is very poor with or without Twal at lock. Both Twal and May can go long minutes and still play at their best so that allows pole and hunt to play more of an impact role.