Again, if you have to go with a starter, it is best with Absol (weaken opponent's set up then take advantage of their discarded supporters via Gardevoir's power). I suppose Stantler is far more consistent, as it allows you to use supporters no matter what (and you know you're going to get the supporter you want), and it actually packs a decent attack once it's done collecting cards for you...
Iono, I've yet to see any Gardevoir/Gallade/Absol in our area, but the combo seems solid (Except for me... I can't build an engine to save my life). On the other hand, Gardevoir/Gallade/Stantler is consistently top cutting over here. Fairly obvious which one I'm going to say demonstrates that it works well...
BUDEW however is a bad starter for Gardevoir/Gallade. It packs no secondary attack, meaning all it will do is fetch trainer cards (admittedly, quite useful, but unlike Stantler it packs no back up move against other set up pokemon). It also has 40 HP, which is snipe-able by rather stupid tricks such as Empoleon's Ice Blade. It also gives a really LOW HP value on the table for Bring Down (VERY bad, as then you'll have to Scoop it up, or lose a prize. BAD). Trainer cards such as Rare Candy are almost vital, yes. But 4 copies of them, plus a good draw power engine... Do you really need much more? Budew just feels too dangerous... Especially if you go first (I get a card with Budew, my opponent rare candies into almost every stage 2 AND Stage 1, DREs, game. :[)