Well, for my part, I had my own 'spellsword' class that I made in Skyrim not too long ago, and it went rather well. I focused on Conjuration and Enchanting as my only magical skills, seeing as I had a plan in mind: Dual Bound Swords as my primary attacking powerhouse, with a pair of Flame Atronachs, later Flame Thralls, as my constant backup. I know, you start with only one summon, but with Twin Souls at 100 Conjuration, which you'll need for Flame Thralls in the first place, it does wonders.
For 'Combat' skills, I focused on Smithing and One-Handed. Getting One-Handed up, and putting a few perks into Dual Fury (Or was it Flurry? I can't remember, and I can't be bothered to look it up just now.), so that dual-wielded one-handed weapons attack faster, made things much easier.
For the 'Thief', I stuck with Light Armor and Alchemy. Yes, I used that exploit, but you don't necessarily need to. With Light Armor, you have some defense as opposed to robes, and that defense goes up with liberal Smithing. If you Enchant it the right way, you have gear that's likely better than Master Conjuration Robes, and you get the additional benefit of Damage Resistance. Add some healing or magicka potions, and you are set for whatever is thrown at you.
I also started as a Breton, which thankfully not only gets the jump when it comes to Conjuration, even starting with the Conjure Familiar spell, but also has, I believe, 25% magic resistance, which is a great boon against any kind of magic user.