Never stuck with the Tales series past the first game, but I looked it up and it looks like Lon'qu and Guy are two very different cases. Guy seems like he's truly afraid of physical contact with women. Lon'qu, on the other hand, is a less straightforward case. According to Lon'qu himself, it's an irrational fear that any woman that becomes close to him may suffer a tragic fate, but I don't think he understands his own phobia 100%.
I have quite a bit to say on this subject (probably not as much as what you wrote though, haha) so I'll save it for when I get around to posting my next Lon'qu picture.
And yeah, some supports are much better than others, pretty much for every character. Even in the same line of supports some are better than others. I ADORE Lon'quxNowi but their S support was such a letdown ._.