I'm interested in getting Sword of Islam because I want to play Muslim rulers but the reviews on Steam are pretty bad and from asking on Discord people say that there are not many differences, just a reskin. Wanted to ask here as well.
with new personality traits abilities that making almost no trait truly negative and also stress I expect if decedence return I expect it to be related to stuff that reducing stress by committing sinsYeah, Christian gameplay is all about the marriage game, manipulating inheritances, inviting claimants, etc., which I find more interesting.
Muslims and pagans tend to already start with easy CBs and much less importance on claims/inheritance, so the idea is that you should be more concerned about managing the after-effects of expansion (Muslims have decadence, pagans have enforced gavelkind, possibly elective, until they reform). Which you prefer is a matter of preference (I far prefer Christian gameplay, but I know some people who are the other way), but in general I find pagan mechanics as a better take on the "easy CB" style than Muslim mechanics, and have a clearer goal in terms of reforming.
It's worth noting that decadence has changed drastically at various points: when SOI was released, it worked strictly on the dynasty level, as a number that ticked up based on the number of unlanded (or insufficiently landed, if you were big enough) sons. The AI couldn't handle it, people complained, and it led to a situation that people found to be unfun. So they eventually changed it to the current system (where characters become decadent on their own, and you tell them to cut it out). I have no idea what CK3's take on it will be.
That was how the original iteration of the system worked, but iirc that meant the easiest way to play was to murder every male member of your dynasty other than your own sons (and then on succession execute all your brothers immediately.) And of course the AI didn't do that so every large Muslim realm got constant decadence invasions.I thought decadence would mean any son without land would become decadent until he has land -- preferably something proportionate to realm size. So you'd have to land sons, and thus weaken yourself and your desired heir.
Only real downside is that Holy wars don't give you the titles, just (pissed off Christian) vassals.
Speaking of which, piety is a pretty big deal too. The two aforementioned CBs come from that, dealing with your Decadent relatives require piety, and you also can't change laws without it as well. The Theology focus is your friend to say the least.