I played in a cover band for many years and got really good at figuring out guitar solos by ear (wasn't any internet or tab back then) but when it came to improvising a solo I would end up playing the same basic licks over and over again.

What worked for me is I taped a backing track of rhythm guitar, a I-IV-V 12 bar blues for example, maybe 10 minutes long or so (no BIAB back then either wink ) then I would take a lick from a solo I really liked and just play that lick over those changes, seeing how it worked over each chord change, and if it didn't, what notes I needed to change to make it work over each chord change. Then start changing some of the notes, adding lead in notes, etc. Pretty soon you have developed some licks that work over all the chord changes. Then find another lick you like and repeat the process. Then combine the two licks, etc. etc.

You must be into blues if you like Albert Collins.

I would recommend Albert King as a good guy to study initially. He had a very simple, but very effective style. Learn some of his licks and see how you can apply them over different chord changes, and what you might need to modify to make them work. With BIAB as you know it's very easy to setup a great sounding backup track to play over.

Most of all, have fun with it!