Hi gentlemen,
I need to drive from Limoges airport to Arles in the south.
After researching my options, I can see several possibilities for the best route, but wanted to ask you for your recommendations, please.
My gut instinct is to go north from Limoges to join the E175/E62 to Clermont Ferrand, then take the A75 to Montpelier.
Is this a good route?
Enjoy the view going that way! 
Across to Clermont Ferrand n down the A75 looks like a fair enough route to me.
The A75 is a great road to drive and crosses the Millau Viaduct of course. The A75 is toll free I think, but there is a toll for the viaduct itself.
As per the 2 prev replies. Assuming youre in a car? No worries, good road, but a bit of traffic around Montpellier where theres some major road works.