A lot of players on the forum or in summits have identified a few major issues with the tower
-It takes too long
-Not enough incentive to do anything but auto it
-difficulty is too dependent on chance
This is a large scale suggestion on revamping the tower that addresses the above while also improving it in other ways.
The new tower should be cut to 9 floors. 6 encounters will be players, and 3 will be bosses. There should be two player encounters before each boss. Matchmaking would not need to be much easier than it is now, as there are far less battles. The difficulty would encourage players to have diverse and large rosters and approach every battle fresh as opposed to just running through with zomm or solaris until they hit a brick wall like barbs. Every Boss floor would have a random selection of 3 bosses (floor 3 has 3 unique ones, floor 4 has 3 unique ones, floor 5 has chromus and 2 unique ones) and would add variety to the tower without creating wild swings in difficulty. The floor 3 bosses would be easy for recharging abilities and healing. The floor 6 bosses would still be easier than pvp but not be pushovers. The floor 9 bosses should be a real challenge that demands strategy.
Shortening the tower and adding bosses would make it less tedious and feel more varied while still reducing the effects of luck.