The Hogue grip is going to be totally up to what's comfortable for you, but here's my two cents:
I put one of them on my CW9 for comfort during range sessions, as that insane checkering was eating up my hands. I loved it, but even as low profile as they are, it changed my grip enough, that I ended up taking it off. I found that on a quick draw, I was coming up off target compared to without the grip. It might work great for you.
As for ammo, my CW9 eats everything I put through it, but I mainly shoot Winchester white box (you can watch Wally World for the 100-rd box at 20-25 dollars) or Remington UMC, FMJ's either way.
My carry rounds are Speer Gold Dot Hollow Points, but Remington Golden Sabers, or pretty much any major brand hollow points are good. I find +P ammo to be a little too snappy for such a small, light gun, especially considering the marginal gain from the short barrel.
Hope you enjoy yours as much as I've enjoyed mine!