Avast is hard to beat and has a really small footprint. The boot time scan is invaluable. Oh, and its free.

Norton is EVIL and should be considered a malware/virus as it takes over your system and slows it down.

SSD does not fragment so disable defrag and pre-fetch in settings. If there is a tool kit for your drive like intel or samsung has, get it and optimize the drive for windows.

Malwarebytes is pretty good. Definitely run it.

Ccleaner from piriform is really handy. The newer versions make it easy to edit your startups. It does a pretty good cleaning of registry bloat without killing windows.

Check your SSD capacity if its 75-80% full your drive will get slow, It has to do with the nature of the drive. You can only use 75% effectively before slow downs occur.

Start removing any nonsense or seldom used programs.

All of this will benefit any windows based computer without killing it.

MSG me if you have questions or problems