Sometimes I feel like my functions fight against each other and sometimes they work together. My life does seem to match the theory that your 3rd function developes in your 20s and the 4th function developes in the 35-50 age range. I just turned 40 and I really notice my 4th fuction start to make itself active.
My top 4, in order: Ni, Te, Fi, Se.
Te often does not play well with Ni and Fi. Feelings and intuition are not logical. Sometimes things I feel or intuit can be verified with logic and then Te will be satisfied. If not there is internal conflict.
Ni and Fi are usually in agreement about things. Sometimes Ni will want something that Fi does not want and then there will be conflict.
Se generally works well with Ni and Fi. Often a piece of art or music (or some sensory experience) will resonate strongly with my Ni or Fi. I often express Ni or Fi through art, in other words through my Se. It is easier for me to express them through art than words, even with my limited talent.
I have noticed an odd thing recently with Te and Se. Going to art galleries and museums, if I look only at the art I can get a very strong Se experience. I will be completely absorbed and feel an intense sense of happiness and satisfaction looking at them (maybe some Ni or Fi entering here). However, when I alternate looking at things with reading the decriptions - a paragraph or more talking about what I am looking at (engaging my Te) this wonderful sense of being happily absorbed in the beauty of the art doesn't happen. Sometimes I will visit twice once to read and once just to look at the pictures.
Sometimes Te and Se will work together to learning things for art or crafts. However this seem to take place in stages, so they are not really both activie at the same time. Stage 1: I am just concerned about getting the how to correctly - mostly Te with Se taking a back seat. Stage 2: The how to becomes more automatic and I concentrate more on creating - Se (with Ni and Fi often influencing).
So it seems like most of the time they all work in harmony, except Te. I have to put Te in the background for other functions to work best.
Ilah