Jarkko mining is dull but it does get better as you improve your skills, a hulk rips through asteroid belts quicker than you can say supercalafragithingamibob. what i do is settle down to a good book glass of beverage of your choice, and mine ,not so dull when its not your 100% focus, or get a buddy and talk crap whilst mining makes its more fun
Mining is pretty much guaranteed income for relatively no risk.
Missioning gives rewards and improves standing with corp you are missioning for which in turn reduces "tax" they take on refining helping your mining become more fruitful.
Salvaging has the potential to increase the cash from missions phenomenally its just not guaranteed that youll get the "good crap
tm"
Exploration which is where i was dipping before i left and when i get used to the game again will take up is duller than mining but the results (if your lkucky to find a profitable site) can be amazing.
Mining and Missioning require very little skills to begin with (the more you progress the better youll want these to be however)
Salvaging takes a little time to gain the relevant skills but is well worth it imho.
Explration requires a dedicated time sink to get all the suitable skills (and have yet to decide if it was worth it, although the ability to use cloaks is cool in its own right)
i guess my point is mix em up whatever gives YOU the most fun from your toon whilst making the cash to follow the upgrade path you choose its all cool.
and as with all things in Eve the lower the security rating of the system the greater the potential for profit, so go to 0.5 (still patrolled by police) and do your thang, but always have that exit point bookmarked