Get out early when there are more jobs going.
I worked in Val last season and you want a bar job no question. You can ski whenever you like and you'll get free drinks in other bars, so it will end up being way cheaper for you, plus you'll meet many more people.
I can't say anything about tignes but as for Val, the best bars for non french speakers (and the most fun are)
Switch Rodeo: run by a mellow aussie, there are normally cool people working there. its normally pretty chilled out, but it goes off on the right night.
Morris Pub: has many staff so its a good crowd, fraser is a nice guy (manager) and has huge nights with live music. You'll need to apply through Mark Warner i think- the website is www.mountainpub.com
Foret Bar: not really a big player on the bar scene, but its really easy work and they do have some big theme nights so it could be fun.
Le Petit Danois: this is one of the most popular bars in town. the girls that work there tend to be super hot and the manager Jarle is a top bloke. apply on www.lepetitdanois.com
There are other bars, but they wouldn't be such a good bet. Bananas is run by a french guy who's losing the plot, Pacific is dead apart from live sport nights, Saloon only employ girls as bar staff, although you could get a glass collecting spot. you will destroy your liver if you work here though. www.saloonbar.com
Unless your an aussie/kiwi etc you won't need a visa and as I say, you'll have an awesome time working in the bars I listed.