In general you can actually eat almost any food while on the hcg diet. The main point is that you'll have to just eat less of it, below the 500 calorie mark for the entire day.
There are some wonderful boneless pork chop recipes available out there. I like using foodnetwork website or allrecipes website. They have recipes for any occasion and any diet type.
You can find some good vegetarian diet recipes by going to any of the following websites www.mayoclinic.com/health/vegetarian-diet/HQ01596 or amazon.com or cookbooks
You can find recipes on any GI site. Good sites to try are the-gi-diet and glycemic gourmet. There are some good recipes that you would not know are low in glycemic.
Any meal that contains very few calories, along with the intake of HCG, is a good recipe for that phase of the HCG diet.
A diabetic's diet should be generally low in sugar and fat. Websites which feature recipes for diabetics include http://www.food.com/recipes/diabetic, http://allrecipes.com/recipes/healthy-recipes/special-diets/diabetic/, and http://www.diabetes.org/food-and-fitness/food/recipes/.
Vegan refers to a 100% vegetable diet which allows for no animal products. There are several good books on the subject available at any good bookstores and many helpful web sites with information and recipes that can be found on the internet.
There aren't many free recipes out there, since the diet is proprietary. However, you can find a huge collection of them at http://freehcgrecipes.com/
A diabetic diet can always be found at your doctors office but a good wbsite is http://www.helpguide.org/life/healthy_diet_diabetes.htm It has a ton of information for food and recipes.
To truthfully answer this question is an answer within yourself. No one person can tell you what taste good and what does not taste good. Its your taste buds that tell you. My advice and answer to your question is experiment try different foods and see where it takes you.
Definitely check out the Eat Clean Diet by Tosca Reno. If you go to the website there are always really good recipes with chicken. Also, Jamie Eason from Bodybuilding.com has good ones too
There are many Baked Potato Soup recipes that are dietly friendly no matter what your specific diet restricts. Low fat and low calorie recipes can be found All Recipes, Food (dot com), and Skinny Taste's web site.
Before you go on any diet, if a significant other told you to go on a diet, speak with your doctor first. There are plenty of sugar free high protein diet recipes on some diabetic forums. Cutting sugar out of your diet can help with weight loss.