Probably not what you want to hear, but I'd highly recommend you wait for the new bow until first season is over. If you're hitting your target OK with the old one, tough it out so you can take your time getting used to the new one.
The last place you want to be to find out 'quirks' of your new bow is at full draw on the bull-of-a-lifetime....example...most newer quality bows have a solid wall with a small valley i.e. you creep just a little and it'll wanna yank your arm off. Doesn't take long to get used to it, but like I said, you want to witness this in your backyard, not drawn down on an animal.
If the old bow is hard to pull and hold back, turn her down a smidge. A couple pounds can make a huge difference (assuming it's not a stick bow). :shocked:
Bows on their last leg are notorious for killing really big animals...I'd give her one more shot! (pun intended)