I suggest you go & visit, by road, a few local strips to see what they do in real life.
>28 days a year use will eventually give you continued rights which mean if the neighbours are kept happy you don't need to say anything to the Council.
A landowner has certain rights to use his property etc. anyway !
Hangars constitute a >28 planning change unless they are really tractor & farm m/c sheds, into which one can also pop an a/c !
You'll need a grass topper or mower for frequent strip cutting and a heavy roller & grass harrow are more than useful, plus of course a shed for them too, how handy.
The balance would need hay cropping to prevent it growing rank. Sometimes local farmers will oblige; or pay a contractor to cut & bale, for selling off oneself. However the latter implies being around for customers and covered hay store or tarp's, I never tried that route yet.
Cattle are discouraged, deer around Sussex seem to skip off out of the way, horses are a no no.
Depending on the field and your choice of a/c & skills,anything from 200 M up to 600 m would do with microlights at the bottom end.
I've been operating happily for 1/3 Century from three farm strips I originated, from nr. Horsham Sx.