I have now made it to Captain and I would like to upgrade to a cruiser class, specifically the Galaxy Class.

My question is: Can it separate?

No it can not.

If you are a gold subscriber, upon max level, if I recall correctly, you will given a token to redeem a new ship, the exploration cruiser refit is one of the possible candidates. It can saucer separate.

No, it's not a gold subscriber ship it's a Z store ship.

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No it cannot

Your much better off with a escort until you reach
Level 50

The cruisers do really poor damage at caption level

Cruisers are low damage hi heal hi defense ships

If your a engineer the escort is a even better choice
For you because your engineer skills boost the
Weak heal rate on hi damage low defense escorts

Its a Z store ship that is available as one of three (iirc) refit ships of which one is claimable as a per character unlock using the token. If you discharge it, its gone forever.

**Addendum: The token is actually a 600 day vet reward, so unless you are a gold subscriber that has clocked 600 days or a Lifetimer, you won't have this option. Sorry for not recalling this important bit of info.

What would be a good way to beef up a Galaxy offensively? How could I make it more manueverable?

YOu don't, it's like turning a truck into a racecar... You can tune it to adegree, but it will fail it's intended purpose and never be as good as the real thing to make it into an attack ship.

The closest thing to that would be the Galaxy-X, the AGT three nacelle version. that comes with a Sovereign Boff layout and the spinal phaser lance.

The Engineering skill Aux to Dampeners can give you a few seconds of higher turn rate.

But your best hope sans C-Store ships for a offensive type of cruiser is the Assault/Mirror Star cruiser you can get at your next rank.

...and at the same time one of the most ugliest.

anyway:

this game is a bit confusing. the "exploration class refit" or what everybody is talking about is the galaxy refit so there is

the default galaxy
the refit galaxy and
the galaxy-x

just for your information. the default galaxy cannot seperate while the refit can. dont recall the galaxy-x can or cannot do this as well.

you will find more confusing names for classes that actually have a name (like defiant class is called "tactical escort".. dont know for what reason they do it like that).

You can't and you don't. You can't buff it offensively without purple quality DOffs which most players don't have at that level, and you can only do so much with the lack thereof of tac consoles and BOff abilities that the freebie ship suffers from. For that matter, all Galaxies absolutely blow when it comes to tactical capability. There are much better ships out there tbh.

As for the maneuverability? EM, EPtE (do NOT recommend), deuterium surplus, and Aux to dampeners are your best bets. But I would recommend against using the galaxy to begin with, and would discourage you from getting any of the c-store variants.