There's no reason to keep carbs restricted to low GI sources throughout the day. Breakfast and post workout are the best times for high GI carbs. Additionally, you're never eating carbs by themselves, you're eating them with protein and fats, which slow digestion and therefor the GI.
Quality carbs most definitely matter! I am at about the same, 350g carbs daily. I eat 6 meals a day and split them up evenly. Here's what I eat for carbs with each meal:
Meal 1 - Oats, bagel, ezekiel cereal or toast
Meal 2 - apple and sprouted granola
Meal 3 - rice
Meal 4 - Finibars (pre workout meal)
Meal 5 - rice, bagel, ezekiel cereal or toast
Meal 6 - cup of frozen blueberries and sprouted granola in my shake
So it's about 50-60 grams carbs per meal. I was also having a hard time figuring out how to get all the carbs in without feeling so stuffed, fruit has been very helpful there.