Apologies for not welcoming you to the forum. I'm sure you'll find much to like here.
If you have heard and like the NHTs, then you should stick with them. If they don't go low enough in your space, you can always add in a decent sub later on.
I have found that 6.5" or so at a minimum in woofer size delivers better Bass in slim towers. That favors the RC-50s. 5.25" is smallish for woofers but if you can pull them out some so they can breathe, any rear porting may help. I almost always prefer a 2 1/2 or 3 way in a tower rather than a simple 2 way, provided the X-over design is done well. This favors the NHTs naturally.
And you are right. The price reductions on the black finish Energys is sick. Any other finishes seem harder to come by at the right price. I know Audio Advisor among others is running very good sales and has some Cherry wood finish as well. If you get the chance, also check out the PSB Image T65s, also on sale at AA. They are very sweet with great balanced sound and feature front porting which makes placement less of an issue.