I think I would detach the main stem from the smaller one and plant it in a much deeper pot. Apparently you can encourage the growth of more roots with root stimulant and use well draining soil.

Aloe vera does this. I reckon if you wait the new shoot will grow up to the same size as the other and balance it. I would suggest too that you water it lot less as winter approaches.They are normally a less bright green than this one. These succulents are adapted to withstand long periods of drought and watering in winter should be gradually cut right down to no more than twice a month..

Of course if you prefer to keep it as an immature plant you can remove new shoots as they grow and pot them on as duplicates. See what Hywel thinks.

my daughter had an aloe like this 3 yrs ago and she split it and repotted it. we now have several pots of healthy aloes.

if you leave it the newer offshoot will continue to grow and then the pot will become more balanced. try propping it against something until it stabilises.

Many thanks for all the advice

I would replant it into a wider, but not deeper pot, and lay stones on the soil surfaceto hold it down, especially a big one to prop the big rosette up. As Sbg says, eventually the offsets will grow large enough to balance it out.