When my horse eventually gets broken in what should i be doing with him just gentle hacking or a bit of schooling i know when he gets broken in i will get told just trying to work out the times scales!?!
Most of ours are backed at 3 and - as soon as they are safe to hack (usually after 3-4 weeks) they JUST hack for a couple of months (mainly in walk and trot - the odd canter - alone or in company.) IF an 'issue' arises, they may come back into the school to work on it quietly.
For example: this little chap (3 year old colt) is just backed and I've hacked him a couple of times which he found WILDLY exciting! He behaved - but pinged and pinged and came behind the bit (which I DON'T want!) So he has come back into the school and is doing 30-40 minutes a day - mainly in walk and a little trot - just concentrating on getting him going forward, calm & straight - and working on getting him to work into the contact.
Another 3 year old (gelding) backed at the same time is hacking every day (in fact was 'the sensible companion' for the colt out hacking.) They're all different and have to be taken at their own speed.