The first thing I want to clear up is the expense of respecing. Yes, pristine recombinant injectors (the full respecs) can be expensive, but can be purchased with in-game money as opposed to just real money (they currently go for 80 red...whew!). But there are lesser respec injectors that you can purchase that are much cheaper. You can buy them with chips from mutagenics merchants in towns.
As far as builds are concerned, the best way to learn is to play with them. I recommend reading The Complete Guide to Skills and Mutations before doing anything else on your build. You can find it at the top of the New Player's FAQs and Guides section, or look at any post by Reaps989 (That's Nysek!) and click on his banner at the bottom and it will take you there.
As for your description of the build you'd like...heck...my build fits that. It's actually a sustain pistol build made for PvP, that has a 193 tradeskill cap and is great for solo PvE as well. If interested, PM me in-game or here.
EDITED: Would need to know your level first, before recommending a level-appropriate build, but I think my endgame build would work for you.
Best of luck to you on your FE journey and don't hesitate to ask if you have any questions!
Edited by KittheRed, 06 June 2015 - 04:27 AM.