If you're thinking of learning CF, only do so with the understanding that it's now a niche product mostly used in government and large companies. Learn it either as a hobby or look at the Lucee source for educational purposes. Even my last company is moving away from CF.
About Lucee ...
I actually helped the company migrate away from Adobe ColdFusion to Lucee due to a chance in Adobe's licensing. We migrated a large, 10yr old, application and all clients over to Lucee in about 1 year.
Lucee is a nice platform but I'll warn that it's not as polished as Adobe CF and there's some difference in features. You'll run into rough edges in their documentation and language implementation (especially the scripting languages). One nice thing I really enjoyed was being able to download the source and figure out how my CF code was actually being compiled into Java. It took me a few days to understand the parts I needed but I actually figured out some issues I was having. I also was able to build Lucee from source, just for learning, which was really nice.