Steamless only works for a few games. If you don't want to use the Steam Client or variants or crack your games then SmartSteamEmu is your best bet.
I don't have Tomb Raider Anniversary but if SSE doesn't work then you'll likely need to use a crack.
Bioshock retail activation is easy to bypass, just install the game, copy the game directory before canceling the install, copy cracked exe to game directory.
Some quick stats out of my games:
44 work with Steamless (Rough numbers, some games will still need a steam emu)
133 work with SSE (Rough numbers since SSE may need to be used with other cracks)
Haven't put up a spreadsheet yet on what people need to do to make their games DRM free since I'm currently reorganzing my games and seperating out the cracks and fixes into a seperate folder structure so they can be easily sorted through then need to see how easily can be imported to a csv via powershell and how useful that will be.