Is he feeling that he'd like a bit of control over his life? Some of these troubles seem to be power battles. If he won't get dressed let him go to nursery in his pyjamas. This isn't to hurt him more to show show him why we have to get dressed, why we have to do it in certain time frames. Act like it doesn't matter and take his nursery clothes with you. He may not let things get that far because he likes nursery and behaves well.
If you don't like this idea how about using a timer, telling him he has until the sand runs out (so he can see time passing) to get dressed and if he needs help to ask for it, leave him be. Once the timer runs out then get ready to leave the house.
With my ds 2 (2) if he doesn't get his shoes/coat ect on when I need him too I say -okay I'll carry on with ds 3 and when you're ready come over though once I get my shoes on we're leaving...He has always come over and asked for his shoes to be put on.
We found the naughty step didn't work with ds 1 (now 5.10) as he became sarcastic 'sorry dog, sorry mummy, can I go now?' and with ds 2 we know it would become a battle over keeping him on the step for the alloted time and therfore, get away from what he did to be put on the step. I could imagine us saying 'now do you know why I put you on the naughty step?' and him thinking 'Nope, but it's been a hell of a lot of fun winding you up...'
I try to get ds 2 to help me a lot. When we're in the supermarket and he's not wanting to be in the trolley I now take a small toy shopping basket and ask him to get items for me, he LOVES it and help to put his 'shopping' onto the conveyer belt. I am going to make him a shopping bag to put it in too.
Talk about how his action make others feel, ds 2 doesn't like to upset people but is begining to see that his action are upsetting people though he does still bit his brother (hard )
Make sure you get out with him everyday, boys are like puppies it has been said many times on here and I have 3 puppies boys and this is so true!