I think that, to some extent, you do the A-check so that you can make a decision.
In much airspace, flying locally - personally I can live without a transponder quite happily - although I might not accept the aircraft with the missing transponder for a long trip, and certainly not if I thought there was a significant risk of going IMC.
Landing lights or nav lights - can't say it worries me massively for a 2 hour flight starting at midday. For a night flight - I'd not accept the aircraft.
No fire extinguisher in an enclosed aircraft. Well, I might be prepared to taxi it to maintenance. Actually no, they can bring the extinguisher over.
I've known a very experienced military pilot refuse to accept a 2-seat aircraft because the secondary altimeter was U/S in the rear cockpit. It was for a spinning test flight and the rear cockpit occupant was part of the crew - fair enough. I'm sure he'd have taken it for a couple of hundred miles navex.
The A-check is there to inform you the Captain, and allow you to decide whether to accept the aircraft - as well as what is or isn't working so that you can operate the aircraft accordingly.
On which subject - you don't need to accept the aircraft unless you judge it's safe and fit for purpose. So, if it isn't, don't. If more pilots would do that, clubs would maintain the aircraft better. (Or, as has already been said, buy a share and join in the task of looking after the aeroplane as you'd wish - most syndicate aeroplanes are much better looked after than most rental aeroplanes.
G