It's not a straightforward set. You probably want a Mountebank as it can just inflict so much damage, especially to a minion engine. Even so you probably don't want to let your opponent get all the minions since they'll just cycle the deck, give you 4 card hands, and play a mountebank or trade route most turns. It's difficult to guess just how valuable the minions are on any particular buy until you get into a game. The apothecary and trade route look really useful in dealing with the mountebank damage but they both add an overhead to the deck. Horse traders look good defence in an attack heavy deck that could fill with green and purple cards. The hoard looks fantastic for a duchy rush but that tactic isn't going to enhance your minions.
The pawn looks weak here and I suspect it's as good to pass as to buy one. One watchtower at the start seems ok, but it's value quickly deteriorates as better action cards enter your deck. The stash has some pluses but more minuses and there are better alternatives to buy.
The pace and balance of the set - well it's quite difficult to judge without playing. Perhaps if you get a couple of quick hoards you could just go headlong for duchy/duke through with mountebanks, hoards, and trade routes. On the other hand, if minions become competitive then the dynamics change, the horse traders come strongly into play, and three piles could run out quickly after curses and minions. Is it possible to just play with horse traders and duchy/duke, soaking up the attacks? I wouldn't like to say. The value of the terminal actions, trade route, horse traders, and mountebank, will vary based on your opponent's play and it's not easy to say in advance which would be best, or whether it's worth taking an apothecary if you get bogged down in a low spending deck with coppers.