I also wasted a lot of time screwing around, leveling up, and hunting for other collectibles, so it’s doable without focusing on collecting entirely.
I was able to collect all 101 combo weapon blueprints on my first playthrough with time to spare, and without rushing a whole lot until the end.
This is a time consuming task, but it can be done in your first playthrough. There are 101 combo weapons in Dead Rising 3, which means collecting 101 combo weapon blueprints.