Can't think of anything unique. First 2 would be my picks.
Doubletree Northbridge is nice. Quick easy walk to Yagan square through the car park and across the road to central area. Has exec lounge. I prefer it to Parmelia Hilton which feels a bit dated and has no lounge. There are plenty of eats in the area, the rooftop movie place is close. DT has a pool. There's the likes of the adult shop across the road and it can get a bit rowdy late at night but I've had a few stays and never heard or been bothered by street noise. Breakfast in the lounge or main restaurant (main more extensive). There's a pool.
Intercontinental is more central than DT and new. I don't think they have a pool if that's important. Definitely get something above a standard room. Felt a bit small, more so in the main bathroom area. Didn't think about booking lounge access and was sold out. Not a fan of the downstairs restaurant out the front and many of the cushions have stains. The upstairs bar for drinks is nice. IC definitely has a more upmarket feel to it. I think the Hilton brands have a more relaxed vibe but that's personal interpretation.
Stayed at Novotel Langley some time ago but was super brief, dumped gear went out for dinner, came back to sleep then left next day. Felt dated and wasn't impressed they hadn't removed a 3rd bed and pushed everything over towards the wall. I don't know if they've had a refurb.
Forget Ibis (although I don't think you're angling to stay there). Really noisy after dark.
Haven't stayed at Westin but looks nice. I prefer DT/IC locations. Apparently the lounge is good as well.
Four points is across from the arena, bit less central.
Stayed at Fraser Suites once which I quite like for the space of the place. There are the free buses into town but ultimately I prefer the more central locations.
There's also Peppers I've walked past. Not sure if they've fully integrated into the Accor fold.
I really like Aloft, but that's not central.