There are hundreds if not thousands of kinds of Silat. Some are internal. Some are external. Some fight exclusively on the ground. Others are long-range stand up styles. Some have a lot of Chinese influence. Others have little or none. Some are evasive. Others practice brutal conditioning that increases practitioners' bone density to the point where they can break others' bones with strikes. Remember that it's an archipelago we're talking about, thousands of mountainous islands where traffic was difficult up until very recently.
The system I practice is from Western Java. It concentrates on close-range standup fighting from boxing range to the clinch. It has groundwork but is weak on ground wrestling. Silat groundwork tends to be a little different because of knives. There's a lot of standard grappling that is a lot more dangerous when a blade or two is involved.
Silat is largely weapons-based. There's a saying "There is no Silat without the knife." Other weapons include machetes, sticks, staves, cabang (something like a sai), whips, small hooked blades, clubs, spears and a number of other things. Each style has its own specialties. It tends to be a village or family art. Very few make their living at Silat. There's a government version with tournament TKD-style sporting rules and costumes. As far as I'm concerned it sucks flatus out of stillborn orangutans.
There's a lot of mystic BS associated with some lineages. Parts of Indonesia have a wide streak of animism which can come out in martial arts. I don't really know anything about that. My teacher is a Dutch-Indo Christian who doesn't have any truck with that sort of stuff. A lot of the woo-woo is simply good body mechanics, sensitivity and mental preparation.
The attitude tends to be pretty pragmatic - take him down, take him out. You don't have time to waste, and every extra second is a chance for you to get injured. If you're injured you can't work. If you can't work your family will starve.
AFAIK there aren't any Silat players active in MMA. Different goals. Different methods. Different concerns. A good friend of mine is supplementing a good MMA prospect's BJJ and Muay Thai with a little bit of Silat groundwork and the wrestling he learned growing up on the Mescalero Apache reservation. The guy was doing well in his gym and was starting to get fights. The Silat didn't make him superman, but it gave him a couple options that people weren't expecting. Of course, tricks only work until people catch onto them. His guard was a little unorthodox and tired the guy in it out a bit faster than usual. I'm not sure exactly what he was doing. He decided that making a living and finishing college was more important. There's just no helping some people
Another thing...
There is plenty of Indonesian nationalism mixed up in Silat the same way that there is in Muay Thai, Judo or Tae Kwon Do. It can make things complicated. There are also some teachers who will not teach anyone who isn't a Muslim. Others don't care what religion you are. Best just to leave religion alone and be respectful of others' beliefs.