+1 (again...)

This has been asked for for quite some time, to disassociate the roll loops from auto loops (thus also giving us roll loops within auto loops).

Many times I've been caught out, hitting an auto loop or hot loop expecting a 4 beat loop, but forgetting I had done a 1/4 roll loop.....big ouch. The only fix for now is to get in the habit of hitting a 4 beat roll loop after you do the tight stuff to reset it. Which sucks.

It's unlikely that you will get the ability to specify a hot loops length individually because it is designed to work with the auto loop length so it is a spontaneous event, like the hot cues are, you should know what you are going to get when you press it (as long as you've remember to reset it lol)
What you are asking for is what the 'saved loop' function already does. If you lock these pre made loops you can adjust them on the fly but they will always return to your saved value when you re-activate them. If you press shift + saved loop, you will jump to and activate your saved loop. You can stutter doing this too like with a hot loop. The only down side is that you don't have is a waveform marker to show you where they are unless you save them at you hot cue points, which is what I currently do.

+100