well, I couldn't get the cease fire even with 7 or higher (maybe even 9)!  I had a trade pact and gave them lots of stuff, and did their missions and put an envoy in their system, which they were want to attack!  I researched everything that would take away different faction penalties.  Maybe that only works for other "races".  who knows?

they didn't like me, but I "liked" them. 

You need to check what both sides of the relationship feel in that situation by checking how your empire feels about them in the diplomacy tree. 

Going to start over, just in case there's a misunderstanding on one of our ends...

• Step zero: Play a game with multiple players and without locked teams.
• Step one: Get 4.5 reputation with a faction so you can offer a ceasefire. Unless it's 1v1 at that point, they should accept.
• Step two: Make sure you have the research to offer quests to other parties.
• Step three: Go to offer a quest. In a the mission window, you should be able to toggle the types of quests (Destroy civ structures, destroy ships, ect). Do so until you find one that says "Send envoy."
• Step four: Send the Envoy quest.
• Step five: Destroy their faction in a rage because the AI never sends you an envoy, despite offering the mission half a dozen times.
• Step six: Repeat steps 1-5 with another faction.

If this -still- doesn't work, well... I have no idea, as I'm apparently retarded, and will tag out with someone that knows more.

Messed around with some autosaves... The second I hit 4.50 rep, I offered a ceasefire. Immediately after, I could do the Envoy quest. My standing with them was ~8, so not really that high. I don't see anything special in the diplomacy tree that could affect it. I have a trade alliance, but I think all that'd does is help raise my reputation level.

Is it really early in your game? I'm about two and a half hours in. I don't know how the AI works, is it possible the AI doesn't know how to make an envoy yet? That seems unlikely, though, I admit, if I can offer the quest this soon.

Frankly, I'm at a loss. Unless something dumb is going on, I don't know what the issue could be.

Also check your faction modifier, even though you're both TEC you get a -5.0 modifier for opposite faction.

The AI doesn't always accept the mission in my experience, it'll just keep timing out.

Research the diplomacy relation modifier techs and give them easy missions that they'd end up completing anyway. Also get the trade pact, both of your relations will slowly go up over time due to trade. But the biggest thing that influences it is how much damage they are inflicting on your enemies. If they are blowing stuff of your enemies up while not attacking you, you'll eventually get a ceasefire and be able to send envoys. If they are just sitting there or attacking you, it may not be possible to get a ceasefire.