Roughest coaster I like is probably Boss. I have much higher tolerance to wooden roughness than I do steel (SLC, Zamperla, ect.), usually I actually like getting the living daylights shaken out of me, it's when ride hardware is actively striking me that I have a problem. Wooden coasters that are too rough for me include SFNE Thunderbolt, Compounce Wildcat, Son of Beast, Predator, Gwazi, and the second half of Zeus. For steel I'm a lot more stingy, anything from a crap ton of headbanging (SFNE Flashback, CW Flight Deck, SFA Apocalypse, SFGAdv Batman), jackhammering (SFNE Mind Eraser, T3), or a horrid rattle (2018 GateKeeper, Diamondback coming out of its hammerhead, Kingda Ka, La Vibora) is certain to get a poor ranking. But with wood, it can do quite a lot of shaking around the layout before I actually find it painful.
I know I'm a huge RMC nut, but most of the wooden coasters I want converted are because their geometry makes for a boring ride, not because they're rough. Boss, Hades 360, TFAP Avalanche, Hershey Wildcat, Cyclops, and to an extent Switchback are all wooden coasters that are commonly considered to be rough that I either enjoyed despite this or didn't even find rough at all.