You sound like you want and need a “Rebbe”, and it sounds like and he’s a maggid shiur, not a rebbe. A rebbe is a person that you have a kesher with, a person that you can talk with about gemora or about your life, even during his unpaid hours. Someone that you still talk to after leaving yeshiva.
However it’s more understood that you won’t have a kesher with a maggid shiur (in most scenarios). Most big yeshivas, the bochrim pack into a room to hear a shiur from the rov and thats it. Even if he would want to give you more time, he most probably wouldn’t be able to, even if he was the nicest person in the world.
This is probably the deciding factor between choosing a big yeshiva to a smaller one. A smaller yeshiva usually has a lower level of learning, but the cheshek is easier to attain, because there’s a connection with the rebbeim. While in a large yeshiva, the learning is most likely on a higher level, there’s a much greater need to be independent.