The fairly new HGI on South 188th Street, literally around the corner from one side of the DT, comes to mind. It was a pleasant property when we stayed there in 2019. You can find the FT thread here.

There are a multitude of Hilton brands with shuttles to SEA. We've stayed at most of them over the years. It depends what you're looking for.

We're satisfied using the definitely dated DT or Airport Hilton for quick overnight stays when they're competitively priced. YMMV.