One thing I would definitely do (if access is not an issue) would be to put up a separating wall between the two ends. Utility room access from the house, workshop access from outside), for several good reasons.
Firstly, it would give you another wall for a deeper bench or machinery.
Secondly, if you are creating smells or dust, it would keep it out of the house, away from the laundry and avoid annoying SWMBO.
Additionally, it would keep the noise down, and give the utility end the same extra wall for shelves and storage.
If access is an issue, then putting up a wall with a door in it. A cheap external door, would provide a good seal between the two halves, and still provide a corner wall on both sides.
Workshop ideas have been discussed on Mayhem here
http://www.modelboatmayhem.co.uk/forum/index.php/topic,56788.msg590303.html#msg590303My small workshop ideas and pics of my small shop are also on this thread, although I appreciate your workshop is narrower.
Loads of ideas for workbenches on Pintrest, you will need to register (free and no spam).
https://uk.pinterest.com/pin/336573772137967525/Lots of ideas for folding workbenches.
https://uk.pinterest.com/search/pins/?q=folding%20workbenches&rs=guide&term_meta[]=workbenches%7Ctyped&add_refine=folding%7Cguide%7Cword%7C4
With a space like that I would suggest a folding workbench, so that you can have more width when you need it. I would also supplement this with a work trolley, like a table on wheels, with storage underneath. Also the bench does not need to be full width, especially for modelling, 500mm might do it, with the work trolley for bigger jobs and where you need to work around the work piece.
Derek's thought about overhead storage is important. I have a low ceiling and I have shelves at above the deck, I am 1.72.
I have a 1.5 m deep, full width, shelf at one end of the garage for bulky storage of scraps. You could get your builder to put on in, if you lose the integral door.
There are also ides for overhead storage here
https://uk.pinterest.com/search/pins/?q=garage%20overhead%20storage&rs=guide&term_meta[]=overhead%7Ctyped&term_meta[]=storage%7Ctyped&add_refine=garage%7Cguide%7Cword%7C2
Put all of your electrics above bench height (1.1-1.2m) and have more outlets than you think that you need. You could even put a separate fuse/circuit breaker box in your shop. If you think your shop will be on wheels, put electrics on both walls. Consider an extractor fan, and a stand alone fan to pump air around the space.
Put as much as you can (benches, work tables, storage, etc.) on wheels. I have a single garage workshop and everything is on wheels except a paint cupboard.
I have a paint cupboard that I built that is only about 300mm deep. More than enough as anything deeper and you start to loose stuff. You may find a cheap bookcase with doors second hand.
I also have a lot of wall storage racks.