OK....Gonna toss out some thoughts on the subject. I have a degree in soil science. (working on a Masters) Here's a few things I've learned while in school and a few things I picked up after 40+ years of farming.
1st. There are no absolutes....No answer is always right....No answer is always wrong. It all depends on soil conditions, weather conditions, and a laundry list of variables, as to what is the "most correct" answers to your questions.
2nd. Tilling (ie OVER-tilling) in dry conditions might just be the WORST thing you can do. Dry soils tend to turn into talcum powder consistancy. A good rain, and you have highly compacted soils that resist further rains from penetrating, as well as no oxygen in the soil.
3rd. You might not have issues with water erosion, but I'd bet you get WIND if you're on high ground. Wind will carry away ALMOST as much soil as water/rain. Tilling in late fall, you'll have enough soil moisture to resist some wind erosion. Till in the summer, and your neighbor will be sweeping your soil off his back porch.
4th. Use ((over use) of chemicals (ESPECIALLY Glyphosate [RoundUp]) is one of the leading causes of todays "RoundUp resistant weeds" If you do use chemicals, practice LIMITED use, relying on mowing weeds in fallowed ground to prevent weeds from maturing to seed stage.
5th. If you do till, even in the fall, it's a good practice to establish a cover crop after working the soil, and until you go to use the ground (to plant a crop) On larger tracts of crop land, crop residue from previous crop often fills in for a cover crop as far as holding soils in place. Cover crops decay eventually, adding to the soil structure.
6th. Manure will help soils, but have some short term negative effects. While decaying, manure ties up nitrogen. Eventually, rotted manure will add to the nitrogen levels, but MOST of the time, you'll need to add lime to nuetralize the effects on soil ph levels. Be carefull of adding too much manure at one shot. Manure commonly has a LOT of weed seed in it too. (especially so with cow manure)
7th. My advice is to NOT take anyones advice too seriously, UNLESS they're "local". What works here in Kentucky might be the worst thing you can do at your location. Contact County Extention office/Soil & Water District office for more detailed, localized info. That's what those boys are there for. They'll be glad to help.
8th. Generally speaking, MOST advice you get on tillage will be deeply rooted in the "givers" equipment inventory....In other words, they'll usually suggest you use the same sort of equipment they're familiar with, and/or what they usually use. Starting from scratch, assembling a list of equipment, and building soils works best when you start with no pre-concieved notions, rather than what worked on someone elses farm 20 years ago....
9th. The single most important thing I can suggest is to START with a soil test. Not JUST NPK....Get a test of NPK, Ph, and micro-nutrients. Without a proper balance of micronutrients, NPK is tied up in the soil. No amount of fertility is of use if the plant can't access it. In the case of my soil on my farm, I'm having to balance zinc and boron levels. N was a tick low, P&K were actually abundant. My corn crop couldn't use what was there, so we kept piling on more and more expensive fertilizers. It wasn't until a test indicated the need for zinc and boron, then adding them to the soil, that I was able to realize the benifits of all the fertilizer I added. Again, get the county extention office involved.
10th. Have some idea what you'll be doing with this soil. Some crops need specific levels of specific nutrients. Some crops can actually be harmed by the levels that HELP others.
Now....Are you totally confused?