Yes soy would work fine... but I find that vegans generally eat Way too many soy products. I would suggest giving rice milk a try - Yu Basmati is really nice, it`s my favorite.
there's not really anything wrong with eating a lot of soy products. Of course variety is always good, but in terms of nutrition, soy milk is the only one with a good amount of protein, so I prefer it for that reason and soy milk is always fortified with calcium, vitamin D and b12, while it seems like not all the other non-dairy milks are. But yes, any other non-dairy milk will be fine.