I am 6 days post op, and did three weeks of pre-op liquids because my surgery got postponed one week. I was allowed two VERY small healthy meals a day, so it's not as restrictive as yours. Here's some things I found helped. Run all my suggestions by your doctor.
Clear Liquids
Isopure Protein Water. Good flavors, no carbs or sugar, and a whopping 40 grams of protein per 20 oz bottle. Several good flavors, but Ice Orange was the best.
Top Ramen flavor packets. Way better than broth. As long as you don't mind the msg, it's great.
Tropical sugar free popcicles. Better than the regular flavors. They are great, and were my staple. Filling, and delicious.
Sugar Free Jello. These didn't end up being as good as I hoped, but they are good enough for a change of pace.
FULL LIQUIDS
I graduated to full liquids. Find out from your doc whether you get clear liquids or full liquids. My full liquid diet post surgery included pudding, yogurt, cream Soups, and cream of wheat. I found some great stuff in this category that I've really enjoyed this week. The biggest surprise was the gourmet soups in a box from Campbells. Portabello mushroom soup was amazing, and better than a lot of restaurants.
Hope this helps. Feel free to PM me with more questions!