My thoughts so far.

So I've played through a few times now focusing on boarding/marines and I have to say that the "Marine Clone" ship is absolutely fantastic. Against everyone except for the Unknown, Boarding can be an absolutely awesome tactic to turn the table on your opponent quickly. If you are able to focus on enhancing marine research, which is absolutely critical for this strategy, and have 2-3 Marine Clone ships sitting around to replenish, you can amass quite the fleet quite quickly.

In so doing, I noticed that research for the "marine boarding shuttle" doesn't seem to work super well. For obvious reasons, you can't upgrade the weapons on the shuttle, but it would be nice if you could upgrade other things, namely the armament, ECM, and drive speed.

Also, I'd be completely down for scrapping the boarding shuttle hangar concept entirely in a future game, and simply buying a pair (or threesome) of boarding shuttles for a set fee that appear and cause hell like the computer does. Getting infinite, free (after initial purchase) marines with the Marine Clones is very, very powerful, and almost feels a little overpowered to me. Sure, they're really expensive, but the though of free marines for the rest of the game (assuming you keep it alive) doesn't sit well with me for some reason.

Lastly, I've also done a comparison of the various super weapons. In all the games I've played, Nukes beat everything else (even boarding) hands-down. A fleet with 10+ nuke launchers is nearly unstoppable.

For comparison, I maxed out a fleet with a bunch of super lasers (aka Death Ray icon) and got totally annihilated by four, yes four, nuke launchers on a pair of enemy ships. When the situation was reversed, I cleaned the floor with some Unknown battleships.

Anyhoo, still really, really enjoying things.

The one "path" I haven't been able to win with is the point defense path (gatling, energy gatling, etc). Now granted, I only play on "legend", but it seems that I can't generate enough firepower quickly enough. Furthermore, I haven't found a situation where you want a point defense weapon other than a laser, because they are truly fantastic when upgraded.