You’re already half way there, because you appreciate you have good staff and if you never forget that good staff do not grow on trees but are an invaluable asset you will be fine.
Good staff also appreciate a good boss, respect being a two way street, mutual respect and you are straight with them then when, as you’ve found, you need to pull someone up, a sensible discussion and it was all sorted amicably.
Good drivers can be left to get on with their work, respect thing again, if you employ a wrong un or an idiot it isn’t the fault of the other staff its yours as a manager and no reflection on them, so sort the wrong un out don’t be tempted as happens in too many places to go the easy route of dumbing the job down for everyone else with memos making everyone else change how they work because the company failed to take action to curb or get rid of someone who should not have been employed in the first place…this tends to increase in frequency if allowed to happen, and ends up demoralising your good staff.
Work should be dished out fairly, some drivers are better at some sort of work than others and vice versa, if you can manage to dish the work out in a way that each drivers does what they enjoy, or are good at, then that will be a happy ship indeed.
Sadly its true that good donkeys go best loaded, if the company grows you often find you’ve got a ■■■■■■■■ of reliable drivers who will do their best, and what can prove to be a growing minority of game players and chancers, in too many places they load the good donkeys up too much and allow the game players to get away with murder.
Much of this depends on how people are paid but if you take the ■■■■ too much out of good reliable people, sooner or later some other company will spot that band of first class drivers and poach them all from you, i have seen this happen myself and i was one who jumped ship along with about a dozen others, none of us regretted the move.
Good staff don’t want special treatment, they aint snowflakes, all they ask for is a fair crack of the whip, and they cheesed of quickly when the sick notes, can’t do this or that, childcare crews, etc earn just as much for doing half the work or hours of the people you would literally be lost without.
Your good drivers might be the sort to take a pride in their vehicles, if so help them to help you by providing a wash down facility (or allow them to use one that is suitable) and provide a vacuum cleaner and any cleaning materials they need, engine oil and windscreen washer fluid available, keep bulbs and other regular items needed in stock, most good drivers can be trusted to and would rather fix ongoing things like this instead of wasting a couple of hours sat at the workshops.
I’m just a driver by the way, and this is just my tuppenceworth.