I cut down 1 colress in favor of a Shauna, or it could be the 4th N. I don't know if it's my luck, but I keep drawing colress in the begining when I really need to set up and neither player has too many pokemon on their bench. Colress is only good in the late game and you can always VS seeker it back when needed.
I get your point with Colress vs Shauna. I personally don't really like to play more than a single Colress in most of my builds. However, filling the bench in this deck is extremely easy, so chances are your Colress hits 5 as early as T1. That's up to personal preferences, though, so I totally respect that.
I added a couple Sacred ashes because I found myself with a hand full of big bats, no baby bats to put them on and a Prof. Sycamore as my supporter for the turn. Since I didn't want to discard most of my bats I couldn't play that Sycamore, but knowing you have a way to recover them makes the decision to discard them a lot easier.
Another option could be Lysandre's trump card, but most of the time, you don't want to waste your supporter to shuffle back your crobats. Also, you want to have a way to draw into your bats during the same turn you recovered them.
Well, both Sacred Ash and Trump Card are indeed options to take into consideration. If I was to add a Trump Card right now, it'd be for the 4th Valley, since with Trump Card you'll re-use them indefinitely.
I added the 4th ultra ball because it can get me Jirachi when I don't have a supporter for the turn. This is specially important when you don't have any computer search and have to cope with Dowsing Machine.
I... don't really get what you mean here, there are 4 Ultra Ball in my list.
However, I'd definitely drop the count to 3 and remove something else (maybe that 4th Valley) for 2 Repeat Balls. They also work wonders here, but aren't as consistent.
I also considered target whistle as a tech to get an extra prize in some match ups, getting back a low hp basic pokemon to kill it the same turn can be fun, but it's not worth the deck space.
Well, yeah, that too. I mean, this deck can use a lot of techs, but there's no room for them, sadly.
I'd rather have a consistent and reliable list than a tech-y, clunky one.