I am going for Caldari because I like missiles
I recommend doing missions for the Caldari navy then. It takes time to build up faction reputation, and they sell some gear you'll probably want eventually. May as well start with them.
I was told shield tanking is better than armour tanking
because armour makes you slower (is this true?)
I don't know about slower, but my experience with both is that shield tanking is tremendously better for a variety of reasons.
In any case, if you're going Caldari plan to shield tank.
I don't mind mining. However, I was also told that doing missions could be as profitable?
The following is my opinion:
Without a week or so of devoted skill training to at least allow you to fly an industrial ship and equip it with decent mining lasers, mining is just not worth bothering with. Don't waste your time mining in a frigate. It's slow, innefficient, not much fun, and the playtime would be better spent gaining not only ISK but also faction rep and actual combat experience by running missions.
If you stick with the game, you will definitely want to be able to fly an industrial eventually. So training to fly one is time well spent. But it's not something you need to do right away. For your first few weeks there will be
lots of skills competing for training time, and it would be much better to invest that skill in things that are immediately useful rather than that require a week of sitting around before you can do something as boring as mining.
Once you
have invested probably about a week's worth of training into related skills...mining is a suitable thing to do, for example...while reading or doing homework. It's basically mindless, and you can mine for a couple minutes at a time (again...don't mine in a frigate) between putting ore in a can and then every half hour or so drop it off.
However...even at that level of skill training, mining is probably not more efficient than spending equivlent time running missions...
assuming that you've spent that same week oworth of training time training non-mining skills, and your playtime running missions rther than mining.
There are several levels of missions, each more lucrative (and difficult) than the last, and faction rep is required to unlock higher levels. Whether or not you do do any serious mining, you'll probably want to eventually unlock at least level 4 missions. Not only are they lucrative, they're efficient for rep-grinding to gain access to faction gear, and group mission running is reasonable thing for a group of players to do to be sociable.
Now, if you're willing to invest
months of 24/7 devoted training time into buying able to fly and fit late game mining ships...plus a couple hundred million ISK to actually buy one and fit it... then at that point, yes...it's possible that mining may be a better money-make than mission running.
But that is
not something a new player has any business worrying about. Play the game for few weeks or a month...and at that point if you really want to get into mining, then maybe think about it. Until then...just don't worry about it.
Caldari
I like missiles
shield tank
Consider becoming a drake pilot a few months down the road. In the meantime, play the game and have fun.