Short form: Yes, I think doing bits of scrap patrol with available moments of time and sorting is a fine way to organize/prepare fabric.for future project. Baggies are a wonderful way to store sorted little bits but they do slip and slide you might want something more the size of a shoebox to put the baggies in. I also found it handy when I was organizing to periodically count what I had and write it on a sticky pad size piece of paper inside the bag.
Longer form: I tried cutting a lot of different sized strips and/or squares (and triangles for awhile) and found that it didn't work so well for me. Whatever I wanted wasn't what I had and it took a lot of time and coordination to get them to work. After several years I gave up on the concept and now don't keep anything smaller than 6.5x6.5" square. My least successful scrap system was having a laundry hamper of small bits. For me it was unpleasant to work with and everything always needed pressing and I had to go through the entire thing just to find the red bits or whatever it was I was looking for.
2.5" (2" finished) squares is a common cut down size and was the most useful for me. There are plenty of patterns that use that size. With the math of the points of triangles, you need 7/8ths for the pointy sides instead of the standard 1/4". That is, if you took your 2.5 squares and sliced them down the diagonal, your (2) finished HSTs would only be roughly 1.5" inches (finished) which is kind of small for me. If you sewed on that diagonal line instead of cut, you would end up with (1) 2" finished HST that would match up with your squares and a scrap bit that would end up about 1.5" again. If you have a specific idea of a triangle based quilt, I would cut down to the size you want instead of figuring out what to make with the size you have!
Clear as mud? Playing with fabric (including cutting stuff down) is soothing to me and often tells me what the fabric needs in the future. Especially when you have a lovely bundle of baby love takes up most of your time
