I find that being able to store hay is essential to making sure that I always have quality forage available for my horses.
On a side note, although your gelding is looking a little ribby, I think your mare looks fine. It seems like you will be all set soon, but I would suggest the alfalfa pellets if you run into this problem again. After recently getting a horse with ulcers and doing a lot of research on feeding, I learned that not only is alfalfa a good way to put weight on a horse, but the high calcium content is also a great way to buffer stomach acid. Since your guys are getting quite a bit of grain per feeding, the alfalfa will really help them process the extra sugar and starch, and is I suspect, the reason why they were doing so well on the alfalfa mix hay. Hope this helps!