Some Questions From A New Player

To add a little about choosing weapons.  All characters will start the game with a pistol and then shortly afterrwards acquire an assault rifle.  If your starting profile is infiltrator or soldier, you will have an early opportunity to pick up a sniper rifle.  If your starting profile is a biotic, you have the opportunity instead to pick up a SMG.  I'm sorry, I just don't know if any of the profiles can get a shotgun at that point.  (This is all before you leave the first (tutorial) planet.  Once you have access to a vendor, you will be able to buy and use any weapon type (of course, quality of any of them will improve as you progress).  All profiles start the game with two weapons slots open, but you can open up to four on any of the them just by assigning points into the appropriate perk area.

Any profile and ultimate assign points into any other profile area.  What the initial choice does is delay the unlocking of some of the perks until after you have assigned 9 points into the general areas of those profile; whereas, in the profile of your choice, you have many more perks unlocked where you can place points right off the bat as you earn them.  This system is far more flexible than the old class system used in the Mass Effect Trilogy.  You can limit your selections to custom tailor a specific style of build or spread out your selections to make a generalist type build that can do about anything.  If you play the game through 2 or 3 times with the same character, you will ultimately be able to fill in all the available perks slots.  Alternatively, you can create several very different specific builds by starting new characters for each playthrough.

As for the name, it's really not much of an issue.  The NPC's will sometimes also refer to Scott or Sara as just "Ryder" even if you don't change their default name.  During the romances, it is nice to hear a first name.  With the CC, I found I was able to create a very nice looking character fairly easily... something I could never successfully do with the CC in the old ME Trilogy.