I know what you mean! I've spent days reading and wasn't signed up! and now I haven't been logged in while I've been reading, tried to reply and found out I was in jail too! A donation to BCT does sound like a possible idea, may it would be possible to add a paragraph when you register to explain yourself.

I built a new PC and then got into altcoins.

i7 4770k & R9 290 

A few of the 290's can be unlocked to 290x variant. If it's just for mining, any of the elder generation 7850,7950,7970,7990 or 280x and above in the most recent generation.

This might help a bit:

https://litecoin.info/Mining_hardware_comparison

Doge has done well and is slowing down a little now.

Earthcoin seems to have gained some good ground pretty quickly.

It's hard to say which will hold value in the long run. The ones that people will accept as payment for goods and services.

Emunie looks technically promising.