1: Are mages a fun thing to play? Well, I think so!
2: If i use Mysty's Balanced Magic mod, will that make it so I can do same damage as my thief? No, not exactly. Individual spells can't compete with the sort of damage you'd be doing with sneak attacks, but mages can use some strategy and get a lot of spells going at once. Set up a rune, lure the enemy in with a bolt spell, then lay into them with some dual cast dps... and don't forget you have illusion and conjuration spells to play with too. The Balanced Magic mod was designed to make mages a force to be reckoned with in combat, but still keep the player on their toes with plenty of spells to use in combination. It's a totally different play style from a thief, but you should be able to kill anything if you're smart about it.

3: Can i use light armour/heavy armour instead of JUST cloth for my mage? Absolutely! The mod adds a slight penalty to magicka cost for each piece of armor you wear (more for heavy armor than light) to keep things a little more balanced, BUT, I also adjusted magicka regen and spell costs based on proficiency so that even a battle mage in a full set of heavy armor can be an effective magic user, and if you choose to wear a dragon mask - you can still get the bonus armor from your alteration protection spells.
4: should i invest most of my points into magicka? If you're relying pretty heavily on spells to deal damage, then yes.
5:Are Bretons a good race to be a mage? They are the one that appeal to me most for a mage atm. Bretons make excellent mages. Really, you could play as a mage with any race in Skyrim, but Bretons and Altmer have typically been strong magic users in previous games and in Elder Scrolls lore.
P.S, I have heard people talking about something called CK for modding, what is that? The Creation Kit, which is supposed to be released (free to anyone who owns the game on PC) sometime in January. This will allow players to create their own mods, and for those of us working with a bunch of hex values... it means we will FINALLY have some tools to show us what's going on in plain English, and give us easier access to data and scripting. Expect a lot more mods to appear once the kit is out.
