Ok, inherited turn. I've read all the replies and I think I have a good idea what to do - after looking at the map I fully intend to go after the Humans as suggested.
The scanner ship sent to Sol is going to take 4 turns. I'll build bombers in those four turns. I"m not convinced I like the BCIII design over the inertial stabilizer design - inertial stablizers almost seem like they were specifically invented for bombers. But, after reading the arguments, I suppose it makes sense. Just... doesn't seem right... Anyway, I design FBOMBER 4.2 with the BCIII replacement. I also redesign the missile boat, and I don't plan to build any of the large designs so I leave those alone for now.
I set most of the planets building ships to bombers and missile boats, but leave two on repulsors.
We are already spying on kitty, but I crank it up a bit. Everything else looks good!
Turn 1 -
Lots of ships the first turn! Over 200 bombers.

Phyco starts on a shield and Zoctan finishes atmospheric terraforming and begine normal terraforming.
Turn 2 - Our spies infiltrate the Silicoids and I'm given a choice of Planetology and Propulsion. I decide to gamble on PLanetology, but pull Terraform +10. In other news, the kitties declare war. Not sure what precipitated this... (Can anyone enlightenen me?) I start building some bases at Escalon in preparation (it only had 4).
Turn 2 - No aggressive moves from the Mrrshans yet.
Turn 3 - The humans disband the non-aggression pact... I assume this is due to the hundreds of ships no amassing mere parsecs from Sol... Ryoun has 22 bases now, so I shut if off trickle base spending. Arietas also has 22, but is considerably more exposed and valuable so I'll keep building some more there.
Turn 4 - Our scanner ship reached Sol and finds:
There's nothing we can't handle with our missile boats and repulsor ships, although I think I prioritized bombers a bit much - I switch a few "bomber plants" to repulsor ships or mercs. I sure do like all the level one and 2 shields... Our fusion bombers should have no problem. No it's just a question of waiting for enough ships - should be another turn or 2...
Turn 5 - Actually, is this enough?
I don't think it's quite enough to take on Sol, but it's plenty for the other two planets. I send this fleet to Firma, the human artifacts planet, while we wait for more ships.
Turn 6 - The calm before the storm...
Turn 7 -
We make short work of those bases and I send in the troops. We have a sizeable advantage in gropo tech, so I send in 47 troops from Anraq, the Ultra Poor, which should be plenty. Note that the human fleet is on its way here... so the story isn't over yet. Nice to separate the fleet from the bases on Sol, though. Also nice is that I can send 28 more merculite ships and they'll get there in time to help defend.
Turn 8 - The Klackons have a fleet incoming to Regulus. I go max base spending augmented by planetary reserve there. Fortunately Regulus is an Ultra Rich and should be ok... I think.
Turn 9 - The Human fleet meets us at Firma. This will be the primary battle of this war...
I am forced to retreat when the missiles run out.
Is it fair to retreat the missile boats and then show up again next year? I think this might be exploiting, but I set the fleet to return again...
I empty the rest of our Resever into Regulus. I hope it's enough to fend off the Klackons...
Turn 10 - Hmmm... might be close
We almost lose the colony to the death spores (down to 10 population) but we are then able to fight off the rest of the ships with our merculite bases. That was really close!
There was some good news... The human fleet left Firma, so it was just a land battle, with this as the result:
We got controlled Tundra and Neutron Blasters, not bad.
Finally, the galactic council convened:
Strangely, the Klackons threw 5 votes our way! Lets see, by my calculations... we are only 2 votes shy of a win! We have 17, and with the Klackon 5, that gives us 22 / 36. Pretty close!
Regulus is down to 10 max population, so I immediately put all spending into Ecology - the next player should re-seed it, probably from Anraq.
In summary: I built a fleet, took the first human world, and ALMOST lost a colony to the Klackons. Note that we aren't actually at war with them.
The Game