Personal opinons aside, the issue with doing a combat-oriented level in Generations is that there is no mechanism to fire off an event when an enemy dies, unless the enemies in question are the egg shield pawns from the Seaside Hill Rouge mission (which won't work so well in a normal stage, for obvious reasons). This means you can't have a door or cage or something that opens when you kill all the enemies in the area like the original level did, so you need some kind of workaround - either leaving the door out entirely, or hiding a button somewhere you have to press to open the door (which would feel very forced imo), or having the door automatically open when you get near it. I would probably go with the latter unless you can think of a better option. (edit: On second thought, I'd probably take out the door entirely.) In any case it's just one more thing that makes adapting levels from other games into Generations a challenge, so good luck.