Need a solid leveling build
FT is enjoyable to me. Pairing the FT with the Elixir Gun is the most logical because the same traits help both. EG is also very useful for the ground targeted heal and the acid bomb that flings you back pretty far. Also, the poison (#3) i think removes conditions on allies. The two trait lines that you want to look at are going to be firearms and alchemy.
Another fun build is the TANKCAT build or however you say it. A lot of engies really like using the tool kit. I like it for close combat because of the shield, the 1200 range pull, and the confusion whack. The trait line that helps that out is tools. Take note that in the Tools trait line, Speedy kits is great for perma-swiftness, as well as static discharge (not sure if it is bugged, though). That might give you the chance to use a shield offhand, something that I miss with my EG/FT build. To reduce cool-down of shield skills and increase toughness while a shield is equiped, you need to go down the inventions line.
As for skills, get whatever you think is the most useful to you. I personally picked up everything besides the turrets (excluding the healing turret, that is good). Look at the gadgets, also. Some people think they are useless because of the long cool-downs, while others still find certain ones useful. See if you can’t start out with getting some kits, since you seem interested in the FT. They are very useful, like turrets, but are mobile.
And the tankcat build is viable for leveling too or mainly pvp? I watched videos on it in pvp the other day, seemed interesting. Thanks for the insight, i appreciate it!