I would like to create a spell sword but I'm not sure what skills to use?

One-Handed and Destruction are your source of offense. Wear Light Armor and when you need it (heavy melee enemies) use Alteration for extra protection. Also, use many of the Illusion spells and you can use Restoration if you want.

Also, use the Lovers Stone for leveling all skills.

Yeah, your best bet would be One handed destruction alteration and light armor. They will work really well togeher and help you reach a level of protection that is near or maybe even higher than a heavy armor player. But don't forget about the other magic schools, Restoration and Illusion can really help in a bad situtation.

And yeah, Lover stone for a good portion of the game since your skill are all over the board.