I’ve worn the skate Levi’s 511s religiously for nearly five years. The ‘Caviar Bull’ colourway are the perfect slim black pants. They’re pretty stiff at first, not because they’re slim but I’m pretty sure because they’re coated in something (or maybe it’s just the fabric blend) to make them more durable. It also means you can iron creases into them and the cuffs stay totally put. I’ve given every pair an absolute beating before retiring them and they’ve always held up for at least a year-plus (and that’s skating in them around 3/4 times a week and slamming more than I’d care to mention). Also as they wear in/get scuffed/fade over time in places the fabric goes a bluey-black rather than that faded rust colour you get with some black clothes.
Uniqlo Kando trousers are good for a well priced and super lightweight trouser.
I’ve got a pair of Ted Baker pants which are dope for formal occasions/non-skate activities. Also a good slim fit but I wouldn’t skate them unless I picked up a pair on sale.
Recently got the Former Discord pants. Great construction and attention to detail. Former stuff might be quite expensive but at the quality matches the tag. (That said the price of their tees is banging to say they’re cut and sow.) Need to get them properly tailored though because the legs are really long, I’d say at least 34” and it might be the same leg length no matter which waist size you order.