I think the lap what someone is on should be displayed next to thier name when the position list of drivers or 'names over cars' is on, a bit like:
Xpowaspa(2)
or
Xpowaspa(2/3)

I don't get why...

No thanks here, the yellow and orange arrows on the track are enough for me, I honestly wouldn't care if someone is more than 5 laps ahead of me, or 10 laps behind.

Ahead and behind is plenty.

Hmmm...maybe, can't really see how it would help anything, just another thing on screen.

The only things I can see it being useful for would be when lapping people (racing for position or not) or if it was a long race and you wanted to know what lap the leader was on. But if you are lapping someone and have the time to check a number next to their name you can also see where they are in the list and know if they racing for position or being lapped.

Plus what lap people are on really won't differ that much, except for really, really long races.

If anything then I'd really like to see everything displayed on the dashboard. Something like this: