Most all whole grain and legume flours are a great and healthy substitute for white refined flour which offers densisty not nutrition. Making the switch is one of the best things one can do to improve and increase nutrition.
I am currently playing with the following subs:
Almond milk over dairy milk... Fat free plain yogurt for dips, spreads, cream/sauces, etc. ... and more legumes, potatoes, eggs and tofu as meat alternative protein sources.
Brandy, raw vegan pasta made with root vegetables, squash/zucchini is very easy to make. All you need is a spiral slicer or food peeler and peel into long noodles. Serve raw as is or lightly cook for a different texture. I say this because you mentioned carbs in pastas/etc... Carbs coming from whole grains are good and shouldn't be an issue. It's the carbs coming from alterned - refined sugars and refined grains that are problemetic. A potatoe substitute is cauliflower, especially the orange cheddar variety - delicious flavor. Ground nuts and seeds can be used in place of breading. Nutritional yeast for cheese flavors in place of cheese... this is used in vegan dishes a lot... liquid amino braggs in place of dressings, soy, etc. Another very important switch - table salt over to all natural sea salt...celery salt and all fresh herbs are great jazzer uppers. Making one's own soups and broths is also very healthy and handy.
"Give a man a fish and you feed him for a day. Teach a man to fish and you feed him for a lifetime." ~Chinese Proverb~