Well Sitka has been a while . Great little village. Check RCl to see if you still tender. Makes a big difference to the start/end of your day. DownTown Walkable. and lots of history.
Juneau. Walkable too but I think RCL still docks quite aways from downtown. Depends on how many other ships in at same time. Good place for a whale trip if you are inclined. Best city and general area tour is the City bus.(cheap) Drivers very helpful with transit. TAke the valley loop .
Skagway. the Railway to Canada . Several options. Book with the ship and get picked up near your ship .... with the train... walk to town a ways. If you book the up&back on the train check on boarding if your train reverses at the top or uses the loop to head back down. If reversing only make sure you sit on the right hand side going up. If the loop the right if you can but if you must sit on the left you will still be on the best side coming down so is ok. Reversing they will change seats around and make the other side available to you going down. The right side going down is what you want for the best views. If taking a bus one way make sure your are the right side going up and down . Down on the right for the train for sure. Skagway is the best place to shop. Least touristy. Long main street take shuttle to the far end and walk back.
Haines> I haven't been there. I drag out some Vcr stuff in a bit.