I tend to agree with Alosso about the caches, especially if you were gettimg more bite with the cheap irons.
Whilst I agree with the G25 remarks, this is expensive and the longer you can wait before another major upgrade the better (on your pocket). In the interim you would be better off having at least 2, probably 3 evenly spaced wedges to fit in below you PW (I am not sure of the distance of your PW).
From TP tees. distance should not be an issue and the cheaper balls like the Tour SD served me well all theough Masters Tier. Usually you approaches will be under a 7I.
Yes the G25 are higher trajectory irons and will give you more stopping power, but even with these and an OK ball, approaches 3.5I, especially to and uphill approach probably will not stop.
My advice, save your credits to upgrade later, and enjoy the game and challenge in the meantime.
Edit - for bite - buy a ball with 2 dots of spin - they cost a little more and distance should not be a huge factor from your tees, but you will notice a difference.
When you get to Masters Tees - then review your clubs.