It's a bit of a mess but
this could be helpful, especially the Leaders spreadsheet. The only neighbor who will backstab at Pleased is Stalin (xml NoWarProb=90 for Pleased). Since he is also a likely candidate for pursuing the infamous Dagger strategy, the probability for a NoWarRoll @ Pleased will then even drop down to 80% for him!
PeaceWeight has no effect on the AI's attitude toward the human player and does not influence the probability to start a war at all. It only determines the hidden modifiers for AI-AI relations and is subject to a bit of randomness for each game (Base + [0,1,2]) but remains fixed after the initialization of the AI players. Since all your neighbors have very similar values for BasePeaceWeight they will like each other a lot --> bad for instigating wars between them. Unfortunately I cannot open the save (locked assets - do you play with default 3.17 or do you use Solver's patch or Dresden's update for that?). The glance screen might give away something about the hidden modifiers (they might be pleased at +-0 visible modifiers), could you post a screenshot? Stalin-Suleiman might have a hidden +5 due to PeaceWeight and WarmongerRespect alone.
Getting along with Cyrus should not be too difficult (BaseAttitude +1, BetterRankDifference +2, SameReligionLimit +4, NoWarProb = 100 @ Pleased). But Stalin is a threat (BaseAttitude -1, BetterRankDifference 0), he and Suleiman don't care too much about religious buddies (SameReligionLimit +2). You might try to avoid to be a valid LandTarget for Stalin. To achieve that you must have less than 8 land tiles adjacent to his territory (might be impossible...). That way you are only a valid target for a pass-3 TotalWar. If you manage to have Stalin <Friendly towards Suleiman and Pleased towards you and let
them share a long enough border, then Suleiman will always be picked as a target before you, no matter how weak you are (pass-1 TotalWar; as long as Suleiman has < 1.65 * Stalin's power).
Good luck -- this is not going to be a walk in Gorky Park...