I'm not sure exactly what it is about happy gay characters and romances (as opposed to
dying,
completely humorous, AIDS-stricken, oppressed, or
disgustingly evil gay characters and romances) in fiction that makes that particular media automatically more appealing to me. Possibly it's the subversion of the usual tropes mentioned above in parentheses that depress me so much, combined with the subversion of the idea that male/female romances are standard and mandatory whether or not they make sense. Possibly it's also a bit of trying desperately to find relationships I can relate to, as the amount of non-tragic non-fanservice lesbian relationships in the kind of media I like is next to nil. I don't think I'll be able to even watch Buffy the Vampire Slayer during or after Tara's death. Fuck you, Whedon!
I slash so much, in part because of the hot and the character dynamics, but in part because I never get that sort of relationship in canon. Either the gay people are presented as nonthreatening clowns and "girlfriends" to the main character women, or the writers absolutely must make some sort of statement about prejudice and the tragic nature of homosexuality every time someone looks at another member of the same gender with wistful lust. I'm leaving out bisexuality for the purposes of this discussion, as that's a whole 'nother barrel of rant.
...the point I'm coming around to is that 'Allo! 'Allo! earns my approval not only for being outright hilarious, but for completely ignoring the mess I described in the above parentheses. It does go for the funny gay with Lieutenant Gruber's obvious homosexuality, but the comedic focus is usually less on his inherent sexuality and more on how disturbed René is by the fact that Gruber makes overtures to him personally. He'd probably have the same reaction if it was an old or unattractive woman. Despite his sexuality, Gruber's still just as well-rounded as most of the secondary characters in the show and his very existence is not played for laughs, unlike most gay characters in comedy shows. When freaking 'Allo 'Allo is beating out most modern shows for tasteful and unoffensive handling of a gay character something has gone horribly wrong. We're supposed to be more accepting of homosexuality these days, and yet I can count the number of gay characters in TV and movies who are portrayed as completely normal people I can think of on one hand.
I haven't done a complete study of British media's general portrayal of gay characters, since my main exposure to it was watching Keeping Up Appearences with my gran as a child, but I respect the show for not being complete morons about the subject.