Depending what type and size his tools are there are the roller tool chests someone has already suggested - then you could move it, prop it up near a wall or something if he leaves it somewhere inconvenient or you need to shift it to clean (or rather, get him to shift it!) There are also a lot of reasonably priced wooden chests with different size drawers so maybe if he had one (or more) of these they could be easily stacked, well organised, and individually would be easier to move/rearrange if needs arise. If you have the room to have one unit/chest of drawers for his clothes and another for tools/hobby stuff maybe that could be the compromise.
My better half and I are, in our own ways, as bad as each other (though we both think the other is slightly worse). We have a bedroom each. I have a lot of books, quite a few clothes and a few boxes of stuff I still have to sort out. He has all sort of stuff including tools, bits of wood, electricals, things relating to the new hobby he gets every few years and buys a ton of stuff for (computers, golf, fishing, painting, panel beating, woodwork, metalwork, leather-work, gardening are just a few) + all his work-related things. If we had a bigger house and/or barns/sheds/workshops he would commandeer and fill the lot. Still, keeps him busy and happy I suppose. We are both stubborn but after nearly 30 years we find ways to compromise and, within reason, try to accommodate each other. I'm toying with a few ideas for a new hobby and he has offered to help if I need a hand buying things, getting set up, having a little work area etc - bless. Good luck and I hope you two can find a way to tackle the issue together. (Must confess I giggled at the thought of him filling the current chest of drawers with his tools and you putting his clothes etc into nice storage boxes)