Bit of a cop-out to suggest that if you do what you're supposed to do you won't have to worry about what you shouldn't be doing!
Did you have a greenhouse or smaller poly before ordering your almost industrial-sized one?
I've had a 10X8 greenhouse for just 3 years now and I've still got a lot to learn, not just because I've never had one to grow stuff in before, but also because your location in the country and your polytunnel's location in your plot or garden can make a big difference (hot sunny spots, cooler spots, humid spots etc.)
Two things are very important, especially with a PT which many of us would envy for its size
- balancing warmth, humidity and ventilation are very important all year round, and I wouldn't personally recommend "going for broke" in the first year trying to grow everything you can possibly think of - start by trying some of the more reliable greenhouse crops (tomatoes, peppers, early potatoes and salad crops, possibly sweet potatoes too.) With so much space you could raise an awful lot of veg and flower plants for planting outside too.
(Note that I haven't mentioned cucumbers - haven't mastered them yet but others find them easy!)
