Cruisers and Science ships, having access to a good mix of science and engineering boffs, should both do a decent job as 'healers'.
I've never quite understood the notion that a science vessel would be better suited to 'healing' though. When a system is malfunctioning or the ship is damaged in some way, engineers would seem better for the job. Scientists aren't completely out of place being technical problem solvers and the like, but engineers seem like the go-to officers for normal maintenance and repair tasks.
Just referring to ships here - as ground-based healers it makes perfect sense (with doctors being science officers and all).
You have a good point, you would think engineer based off the name would take care of repairs. To me the discription given to each class didnt really match up with that idea. I looked at it as the enginner had the ability to maximize performance, like maybe even a skill that increases your total HP by a % per level, making it the tank since you could have at lvl 9 say 20% more HP then any other class. Obviously I have not played engineer to even know if such skills excist..
I am happy with the responses I have gotten, I at least know what I need to do to head in the right direction of playing the role I wanted to in this game. Who knows in time maybe they will make it so that each class is able to support themselves while playing other roles.
Science ships can really be specced (spec for me refers to BO skills, captain choice, equipment choice) as a shield tank or healer.
Escorts can be specced as a dps. You can get some defense and/or healing with some different choices, but really that's it. That's what you get though for being able to use MKIII+ cannons.
Cruiser can be a hull tank (and a shield tank too, but science does that better) or a heal tank.
I'm not really sure if there is an advantage for healing between cruisers and science ships end-game. They can opt for very similar BO slots. Only potential difference is you get the option for an additional science BoFF instead of an engineer with science ships. If there's a difference in end-game abilities for healing between science and engineer BoFFS, that would prob. be the difference.