Not sure when you have been told Blocs 3 will be released. Only thing I’ve heard was later this year. All the sub releases are free (2.4, 2.5.1, 2.5.2). I would guess if you purchased just before a new major version, that it would be free(@norm).
Since you came from RapidWeaver ($99), running Stacks ($49) with the foundation framework($99), plus other add-ons and stacks ($???), don’t think Blocapp ($79) is that much to invest.
I have both; I think Blocsapp is much more modern. I found it easier to use; you have to be open-minded, some rapidweaver users get set in there ways. It’s not as mature; the API now is open for third-party developers. The first was just released last week (by a RapidWeaver Developer). I’ve had Blocs for about eight months, and have seen more activity, and improvements then RapidWeaver has had in the three years I’ve used it.
If you can do it in RapidWeaver BlocsApp should work. Blocsapp does not have a publisher (FTP) built into it. That’s good in my opinion as seems like the RW developers spend more time fixing and addressing publishing problems then they do working on the base product.
@eldar has some paid training courses; If you want to get up to speed fast on Blocsapp, I would have a look. The getting started are free, and I would recommend the Blocs Core Training for you since you know how to build a website.
Many CMS options covered by above reply. Pulse (also available in RW) is one.
If you have any other questions for me feel free to ask. There are quite a few RW users who have switched, and a few of the Developers are working on Brics.