I also agree to allow the player to disable surrender, but honestly, I have not witnessed any of these bizarre surrender scenarios that other players have listed.  All my opponents surrendered with only a few planets left after I sacked their capital.  I also had as many as 15 more planets they did and an economy about 5 times greater than theirs, so I think their surrenders were quite reasonable.

There was one early surrender where a hard AI attacked rogue ships at a Terran planet with his first free capital ship and some frigates.  The AI lost his free capital ship and all his frigates to the rogues (ROFL).  When an allied AI showed up at his home planet with a capital ship and began attacking his structures, the AI surrendered.  Again, reasonable IMO.

I hate how they surrender.  Im having a hell of a time doing the civic-only and military-only achievements (only ones left for each race) simply because I dominate an opponent and push him back to his base/stabilize my borders /box him in and then he surrenders after I spend a half hour researching ad nauseum.  Quite annoying to be honest.  Ive had it happen in FFA's with the enemy having 5+ planets left and in 1v1 where he has all kinds of money left (based on end game stats), but his capital ship was destroyed, so he quit.  it's like playing a real human in how petty the computer can be with quitting.

I agree with kirby that the AI quitting does simulate petty online quitters quite well, sometimes it gives up a logical times but here are other times when you capture a dead asteroid or something 3 planets away from their home and they quit.

I finished a 3 Hard AI game against myself the other day on the biggest mulit random map. Not a single surrender even when I took the very last planet, but usually AI surrenders way before it seems logical. Ironclad support has pretty much stood by its previous statement I have posted.

I have sent them several issues with game 3 of which are messed up resources after aquiring many planets if you try to mouse over the said resource you will get a bunch of planets at the end with no numeric values assosiated with them, along with AI is very crippled since starbases have been introduced. 6 hard AI team locked against me usually attack only 1 or 2 starbases and never able to destroy it. Its be over 1 month and there has been no confirmation wether they will fix it or not, but they have confirmed that they will not fix the problem with que lock of varasi ship building. Third one is that in big games toward the end the game gets so slow, but if you quit game and close it to desktop and load game back up its fine for about 10 to 15 minutes then gets slow again, I do have an offical response from ironclad stating that the expansion adds so much new stuff that its not proper for me to think the game should run the same as before entrenchment. It is obvious there is a resource problem, especially closing game fixes issues and what is all these cpu/memory intensive things they have added with the expansion (1/4 quantity of other expansions 1/2 the price, alot of bugs that expansion should have never introduced unless your dealing with spegetti coding) I love this game I have played sins since the beginning and i love the starbases, but since upgrading to entrenchment there are soo many bugs that makes the game very unenjoyable and there is no response on if it will be fixed or not and the AI is now worthless. I will give it another week or two and request a refund if there is no confirmation of forth coming resolution.