It's likely that if employed by the likes of RyanAir or eJ you'll probably ( read, 'almost certainly' ) annually fly more hours & sectors than you would in the same period of employment with a charter operator - i.e. looking to actually achieve the 900 hour annual flying hours limit - and as a FO with a 'low cost' airline you will probably earn more money too ( if only because you work more hours and that their starting pay is higher ) albeit that some of the very senior blokes in charter airlines are also 'doing very nicely, thankyou'.
Then, as a result of year-on-year flying more hours, you'll probably be in the frame for a command a lot sooner than your contemparies at a charter airline ( subject to all the usual provisos w.r.t. being capable & suitable enough ).
Lifestyle wise, working for a scheduled service carrier
should provide you with a fairly stable roster. The difference being that the machinations of the charter market tend to result in a lot more commercial changes and ergo roster changes -
Aside - From my time at GoFly the low-cost sectors were typically, on average, 1:48 long, whereas with Astraeus the average sector length is 3:08 - that said, I can remember being pretty whacked after a week of back-to-back sectors when I worked for GoFly ( whereas at Astraeus it's a lot more gentlemanly, usually ).
Working as a pilot for a charter airline is likely to expose you to more, dare I say it ( and tin hat on ), 'challenging' airports than the typical 10,000' of concrete with an ILS on each end that the scheduled service blokes get to go to ( and before my scheduled-service bretheren attempt to take me up on that, please remember that I've also done 'scheduled-service', and yes, it too can often be very 'challenging' ).
I have yet to do a Malabo trip ( but I've had all the jabs for it, e.g. yellow fever, etc ) and will do one ( or maybe quite a few ) just as soon as I can relinguish some of my more pressing office duties - I'm quite a fan of Africa.
W.r.t. salary might I ask you to have a look at the
The Professional Pilot's Job Network as trying to compare who'se getting paid what is akin to trying to compare apples and oranges - there's a lot of smoke'n'mirrors involved, with airlines often trying to make it appear more than it really is.
That said, I'm not sure precisely what ( if any ) salary differentials apply at Astraeus w.r.t. people who are low on experience but who arrive in the door fully type-rated, e.g. I know that the PPRuNe cadets were initially on a reduced salary ( about £27k if memory serves me right ) - as a function of the opportunity which was provided to them - but, and I might be wrong about this ( I'll ask hamrah to confirm ), I believe that one year on they are now on the standard FO salary of about £36,660 + plus duty pay ( somewhat variable at about, say, £2500 pa ) and thus a total of about,say, £39k ('ish) - but some get more for training responsibilities, etc..
Hope this helps.
Ps. If you want my advice, join a low-cost airline first, get loads of handling ( due shorter sectors ) and hours ( as they'll work you really hard ) and stay long enough to maybe get a command, and then have a think about joining a charter airline to broaden your horizons still further.