not keeping pleuros in community but have in the past , kept with arowana (silver) arowana (black) Florida gar , and assorted American cichlids with no problems at all ,unfortunately this we back when i didn't have a digi cam, i have also successfully kept marulioides in the similar setup, and Micropeltes upto 2ft with some large gars and a rtc and some veija
my current set up mixes 5 sh with a whole assortment of things from arowana to mbuna ,
most of the time (and i did say most not all) snakeheads will only attacked something if they see it as a threat to them or food (i.e i will fit or nearly fit in there mouths) there is of course the exceptions ,you will always get hyper aggressive fish or hyper aggressive species, maraula and aisiatica (think i just got luck with mine) come to mind , if you do mix just keep there tank mates a lot bigger than them and nothing hyper aggressive its self , also have an escape plan ,ie another tank or someone to take of hands if needed , iam sure one of the guys on here has posted a vid on you tube of marulioides (large) that he keeps with angels . if i find it i will post the link up