My experience with that aloe is that it is a good container plant up until a point where it starts getting tall and top heavy, falling to the side, going everywhere... and needing to be pruned. That is probably more of an issue sooner indoors due to the lower light. Aloe ciliaris & similar plants can easily take over any size pot over time.
So actually I would think it might be best to avoid a companion plant, just to avoid undue competition. This of course depends on the actual location and care. The trailing plants that Paula has mentioned could be a good match because they would grow relatively low compared to the aloe, and not require any special care.
The ciliaris hybrid I put in the ground here is growing above a set of smaller aloes (brevifolia, Crosby's Prolific, oficinalis, juvenna) which are a nice contrast in habit, but still need to be liberated every so often by hacking the ciliaris hybrid back, so they get some light. The situation is quite easy to manage by pruning, actually. Otherwise the climbing aloe tends to grow into a large amorphous bushy clump and overrun the stuff around it.
