Eddy- Yes the game is ready. Kerb is going through the suggestions lists now since the game is very playable.
Note only fights with lots of battleriders (35+ riders) are cpu hogs because this game tracks everything and bring down the frames (10fps is my lowest but my normal is 30-50) but other than that combat and the game runs smooth. Kerb will continue to make things run smoother. Turn times are fast and so is switching between menus.
Multiplayer is very fun (though gamespy is kicking the bucket ie you can only do direct connect right now) but Steam multiplayer is coming this month (thank god).
Yes the ai still needs work but its up and running. Remember this is a Kerberos game so you can expect them to keep working on the ai. Every 3 weeks we get a major update and hotfixes every week if they are needed. No one else kicks out updates as fast as these guys.
The mission system is different but man I love it over the old system. Fleets are not throw aways like in sots 1. Naval station placement (move your fleets here and keep pushing forward from your new base of operations), admiral sniping (keep them safe or your fleet retreats back to base and you have to give it a new command ship and admiral), multi fleet attacks (you can only control 1 fleet per fight so make it a multi fleet attack so you get multiple turns to wear down your enemy), etc are fun.
(so i have 3 fleets, first combat turn fleet one goes, then fleet 2 on combat turn 2 and then my assault shuttle fleet goes on turn 3 and quickly burns the worlds down, you get the idea design you own combat strikes and you could do some mean things).
Hey want to colonize that world, load a fleet full of colonizers and launch it, later it will say hey colonies up but do you want us to continue work on it, yes or no (you can add other colony fleets to support to speed it up too after the colony is founded). No more colony ships being used up.
You can have repair and support fleet sitting out of fights waiting to come in to salvage and repair after fights. 1 Salvage ship = 3% chance for salvage so its better to have a full combat fleet (1 or 2 supply ships are good for a fleet). ie you have 2-4 combat fleets fighting in a system and the salvage fleets sits out of the fight at the system since you pick who fights what each turn and salvage ships are squishy).
In the late game you can have dread support fleets that take care of your combat fleet supply needs. Early on not really possible ie those early fleets need a supply ship or 2 but later down the road ie antimatter, supply techs, you can finally do this so you can have a full combat fleet.
Combat fleets work in 5 ways, (note certain admiral perks are better for certain missions)-
http://sots2.rorschach.net/Admiral
Patrol- guard this system (rarely if your fleets are so fast aka a huge morrgi fleet you can defend a neighboring system too but this is rare and you have to have a REALLY FAST fleet). Note if you have a fleet idle in system it will defend but if the enemy fleet's admiral has better stats than your admiral I believe he has a better start (reaction time, evasion, loyalty,... you get the idea).
intercept- see a fleet coming and your fleets are faster, stop them in deep space.
Strike- Attack this system or target for 1 turn.
Survey- scan the system, if you have a fight and don't win your survey is cut short. So you bring more fleets next time with patrol, strike, invade mission setup to clear the system out and then survey (you could survey with multiple fleets and win then you can survey the system). Its possible for this to become a headache if you have really bad luck but you adapt and bring bigger fleet(s)

Invade- Keep hitting the system until supplies run out or you win (endurance = how many turns you get to do a mission so faster fleet and better supply fleet gets longer missions/ farther targets)
Other missions-
Colonize- colonize world
Construction- Build station
Relocate- relocate fleets to the front lines or areas that can speed up certain missions like colonize, build stations, etc... You can also transfer reserves between systems. If you build naval stations you can have more fleets and reserves at that system. Build more modules on those naval stations (upgrade those naval stations) and hey more logistics!
I think this will help you for missions-
http://sots2.rorschach.net/Missions
Seriously I don't know why people hate/scared/don't understand this system, yes new way of doing things and once you wrap your brain around it, its way better. You can easily track your fleets and keep them working. Keep pushing forward, build naval stations on the front lines and move your fleets up.
Community F.A.Q. for Beginners-
http://www.kerberos-productions.com/forum/viewtopic.php?f=37&t=35957
Small questions and answers thread-
http://www.kerberos-productions.com/forum/viewtopic.php?f=37&t=31083
This game has one of the best combat mechanics in my opinion (yes some areas need little more quality of life issues to be fixed but its all there). You never know what cards your dealt (combat wise and system wise). Galaxy also wants to kill you (they know where to strike you at your weakest points) and most your neighbors want you dead. Da weapons, dat tech forest... The ships are damn beautiful and the system look great also!