Never does hurt to advertise (it's like a win-win situation), but it's not the reason that Sakurai puts characters in to begin with, that's the only thing I'm trying to get at.Even according to these bullet points you linked, this is during the period where Sakurai is specifically looking for clones. Yes, Roy was considered more different for his fire, but you generally at least want a clone to have -something- to differentiate them from the base. It also says in those bullet points that Wolf was rejected for Falco because he looked too much like Fox, but he was added later in Brawl anyway. Now, this is conjecture, but doesn't it also sound like it would be kind of rude of Sakurai to not include Roy after the developers show him the new Fire Emblem? After all, it's just a worthless clone slot, and it does help to advertise.
As for Lucario, isn't it confirmed that the Pokemon Company specifically called him up and told him to include him? Sakurai himself seems to value the 1st gen, otherwise he wouldn't put a new 1st gen rep (Pokemon Trainer) when the original games are so old.
I honestly haven't seen any proof in PC calling Sakurai up for really anything but if it does come up I'll be sure to add it to the directory. Sakurai has gone on record saying that Pokemon is the hardest series to work with (from a gameplay standpoint and fitting in with other franchises) though.
As for PT Red, there is evidence that he wanted PT in Melee, the Pokemon he uses all ranked high on the Melee poll (including Ash aka Red) and he also stated that Charizard would be an interesting addition too. Despite that I guess it could be assumed that with FRLG the chance to put in the main character of the series as well as other popular Pokemon (aka Charizard). There isn't any real evidence that he has a bias towards Gen 1 (that's not to say it isn't a funny coincidence) or any other Gen for that matter.