It seems to me that the most important gay relationship issues would be the same as straight relationships. The issues would be trust, honesty, fidelity and companionship. As with straight couples gays in a relationship would have to really like each other, as well as love. The only important issue in gay relationships that is different from straight couples is social acceptance. While society continues to openly discriminate against gays and gay couples, gay relationships will never bloom. An open society would not see any difference between gay and straight. The only important gay relationship issue I see is the inability of society to be able to include gay relationships without reservation.
Gay relationships will be full of the same stuff that straight relationships have. Partners will love, and fight, some will cheat and some will separate. There
is no difference between gays and straight, because we are all people first. Being gay is but one facet that makes up a human being, gays and straights are more similar than either side would care to admit. So the important issues in a gay relationship will be the same as straight people because except for sexual preference we are all the same. One day maybe, this society will accept this fact and extent to gays full equal rights.