Hey Don. A Rollant 46 is a bullet-proof little baler. Low on the maintenance too. We have one that's done way over 50 000 bales with just normal maintenance (a bearing here and there, new set of chains every year, etc.). In our hills, we usually have 100 hp in front of it, but it'll get by on 75 too in straw. I'm guessing you can run the baler itself on about 50? 

You can tie a bale that isn't full yet, but usually it doesn't work very well. What I will do in fields that suit it, is to drop the first bale, then turn around and go down the next row the other way, etc. That way you end up with a few straight lines of bales in a few locations on the field. When using twine, you have a good half minute or so while it's tying the bale. I've also used that time to drive around and group the bales closer together. You  could also consider something like this: http://www.youtube.com/watch?v=oG4dnyyubcI


Let me know what you decide to do. Personally, I think you'll find a way to group the full bales much more simply than finding a way to make (and transport) bales of different sizes. But, of course, I'm not 100% sure what your'e planning to do once you've made them. Anyways, I'm sure it'll be a smart idea, as always.