The vaginal opening is comprised of muscles that can be contracted and relaxed. Comfort during intercourse corresponds more closely with the ability to relax those muscles, and with being well lubricated, then with the size of the opening. Techniques that increase relaxation, such as deep breathing and calming music, can help.
Any surgical procedure can lead to irritation or scarring that can cause its own problems and thus medically we do not recommend the routine removal of the hymen prior to marriage. A woman experiencing persistent discomfort should first raise the possibility with her doctor of consulting a urogynecological physical therapist. A therapist may be able to help with bedikot and better prepare the kallah for marital relations. See our article on sexual pain disorders for further details.
Halachically, however, a hymenectomy is permissible if necessary. If a physician can state that the hymen was completely removed by surgery or due to injury, a woman does not have to keep the rules of dam betulim.