First time builder here about to get started this season. Thank you for all of the info, it's been very helpful. I made and scrapped several plans based on a lot of conflicting info found online but this has been consistent.
After much amateur surveying by two people we staked out a 25' x 50' stretch of yard with a 6 1/2" - 6 3/4" slope from the highest corner to the lowest. No crests and only a few minor dips in between. It was initially set at 30x60 but eliminating 50 sq ft saved a nasty 12" variance. The only particular drawback is this piece of yard is in the front so it's for all to see, better or worse. I have 2.5 acres mostly taken by trees, drainage ditches, gardens and a septic leach field, it's this or nothing at present. We do live in a rural area so it shouldn't be a neighborhood offense as it might be in the suburbs.
I am sure I will have questions, hopefully I will have some good results to share.