Defensively Adams is going to make a huge difference positively for this team. Whether backing up Sengun or starting he will change the team for the better.
Why don't you ask Udoka what he would do. These trade ideas never take into account what the coach would want. Ever. Even considering that Udoka would trade a healthy Adams for some assortment of garbage players is assuming he is a stupid man and only looks to collect as many players as he can versus quality players.
Landale is an interesting Rocket. This coming season is the last one guaranteed, the next 2 of his 4 year deal with the Rocks aren't. That would make him a valuable chip to toss into a deal at the deadline. Of course, much of last season the Aussie was recovering from an injury, but seemed over it towards the end and was far more active. In other words, we might see your scenario play out. Time reveals all!
Did Adams practice along with the team at the new facility? Stone said 15 players participated in practice on a Locked on Rockets video a while ago.