This should be in tech log I would say.....
And being SLF I should not really comment, however I would say the following....
If your not happy with the taxi instruction you have the right to decline as pilot in command (you are in charge of safety of the plane) and request an alternative - if what is offered does not suit you dont take it.
If you were RHS, and you were uncomfortable with the decision made by the PIC the discussion should not be here but with PIC. It will always be unfamiliar the first time !
In general I would expect your right that the more distance you have for takeoff roll the safer, but economics does not always work like that - it will be a calculated judgement of safety over economy to a reasonable level I would speculate.
Sorry for my 2p worth.