The best generic with a professional context is Lecture.pro. Lecture.tv has 1 bid on Sedo. e-Lectures.com sold for $2,000. eLearning is a boom industry so this is probably the one to keep. The downside is Lecture is not a premium domaining word and 1 bid on Sedo and previous sale is probably not going to be enough to sell the .pro.
The strongest brandable is Galaxy.pro. If you put "GalaxyPro" into Google you get 218,000 uniques which is a good association score. There are alot of bids on Sedo for domains with Galaxy in. Galaxy.fr has 2 bids and iGalaxy.de has a bid so the keyword has international appeal. I have sold 2 brandables, Touch.pro and Switch.pro and probably if they were appraised, alot of people would have advised me to drop them.
Your annual renewal bill is $440. Rather than spending that for a couple of years, you would be better off buying dropped domains on Snapnames. For example, Escrow.pro sold for $750 and Appraisal.pro sold for $600. I think there is more likelihood of selling a .pro like that for $3,000-$5,000 to an end user than selling a domain in your list for $1,000-$3,000.
I assume the domains in your list were hand registered from the WHOIS and that is not the best way to go. I have dropped Computing.pro and Ancestry.pro in the last couple of weeks, these are stronger keywords than the domains on your list so have a look on Snapnames. Therre have been some great drops on Snapnames over the last couple of years and saleable .pros like Tennis.pro, Chess.pro, Politics.pro, and Stockmarket.pro have sold for very affordable prices. I bought Local.pro at Snapnames for $59 and sold it for $3,500.
I am still dropping .pros I registered from the WHOIS in 2007. With hindsight, I should have stuck to drops, the aftermarket and Snapnames.
