A gun on an Astero? What do you leave out? The cloak or your Core Probe Launcher? Do you plan to do uncloaked exploration? That would be a waste of this hull, in my opinion. The Astero without the ability to warp cloaked… sounds not like something to strive for.
Combat Anomalies, PvE. To learn the ropes.
I won’t be the same if you do this with a friend on the test server, but probably as close as you will get.
But consider this: Someone who is ambushing you while you are hacking thinks he has at least as decent chance to kill you. So you will exclusively end up in situations where you are in a worse position to fight than your attacker. I recommend to read in this thread:
Combat Anomalies is the answer again. An Astero can probably do nearly all of the ones you find in highsec - if you use drones and stay at range to the NPCs. You don’t want to brawl with an Astero in pve, usually.
Augments? You mean Implants?
Cloaking IV, so you can use a Covert Ops Cloaking Device II that will allow you to warp cloaked.
Train those as high as you like. These are skills that will benefit nearly every ship in the game: The Magic 14 - EVE University Wiki