Re: solo training
I find that having a set pattern to work through, rather than "just practice", makes me less likely to stop midway through. Ki Society teaches a lot of solo exercises: twenty-odd practice exercises ("hitori waza") showcasing various movements useful for aikido, and a seventeen-part routine ("Oneness Taiso") which mainly works on rhythm and smoothness of movement. I do these when travelling; at home I add some memorized jo and bokken kata. I think they are hard to learn from written descriptions, though.... Have you looked into buying video tapes that would provide some memorized patterns appropriate to your style? While it's hard to actually learn aikido from tapes, they can give you some drills suitable for home use. Donovan Waite's ukemi videos are awesome.