Sweet potatoes are awesome, low in GI scale, but i know what you mean the taste can get to to you after a while.
Oats are perfect, on high carbs i will mix them into a smoothy with protein powder and fruit, taste awesome, sensiable amount of calories.
I keep away from bread, all types, it just bloats me out. but thats just me.
My fav is brown rice, i know sounds and tastes bland, but i will mix it up with spicy chicken, self made, tastes great and you just feel so healthy and full after. A pumped full.
High carb days are awesome, sometimes i have a 2 meal blow out, chicken shish kabab or indian, still high protein but way to many colaries, i wake the next day i feel awesome and haven't put on any bodyfat.