Taking your luggage onto the lightrail to go to a downtown hotel isn't that big a deal. People do it all the time. There are extensive bus connections from the light rail stops downtown, and of course cabs-a-plenty, but many of the downtown hotels are very easily walkable from one of the light rail stops. It may look far on the map, but it's usually not that bad. I wouldn't bother with a cab for a hotel less than 6-8 blocks away, but that's just me, I guess.