Hey Dan, yeah it can be more difficult when these serves come in with topspin because you can’t work against the spin to avoid the ball going off or popping up high. Definitely working a strong forehand flick will help you in this situation so you don’t have to push the ball and give a weak return as you said. Also if you do try to topspin the ball you need to take it a bit earlier than you normally would and think about hitting more forward into the ball to avoid lifting off the end. For sure targeting the elbow is still the right thing to do as well, if you can’t hit a really strong shot then playing into the body or elbow is even more important.
I hope that makes sense and helps you! Tom 🙂