I think its majority him being a brat! Little bit of under-confidence, but not sure what I can do to boost it? A few weeks ago I took him on holiday and rode him for a week solid (8 hours a day!) and he napped all the way...awful at first, then much better on the last day, but still not an easy ride!
Groundwork. You need to control his feet. Start off with leading, backing up, yielding front and backend exercises.
I suspect leading, backing up, and forequarter yield may be an issue.
leading (and a bit of backup):
http://irishnhsociety.proboards41.com/index.cgi?board=usefulinformation&action=display&thread=310
HQ yield
http://irishnhsociety.proboards41.com/index.cgi?board=usefulinformation&action=display&thread=325
FQ yield
http://irishnhsociety.proboards41.com/index.cgi?board=usefulinformation&action=display&thread=305
Good luck.