If you want to avoid the risk you can go over on sisi and use /booststandings to practice them, there is something of a learning curve to missions, but I think once you start getting them down they should start to feel pretty easy after a while.
For ship progression I’d suggest a mach first, that will work to run and eventually blitz the normal mission set. From there the garmur and daredevil are good next steps, the garmur can run all 4 team burners, and the daredevil can run several burners with the same rigs, just need to swap a few slots. Then there’s a speed fit DD, a hawk, a wolf, and you should be all set for the frigate burners. The bases are a bit more expensive, I wouldn’t suggest spending a bil on any of these, Blood base uses a pretty standard purger gila, Serp base can use a deimos for safety or a vaga for speed, then the angel base is pretty easy in a vigilant.
all my setups can be found in this post:
And if you notice I didn’t even mention the gurista base, but if you really want to run it I suggest the vigilant. You’ll want to be decent at cap and heat management to make it through the whole mission, if you think things are going bad you should be able to warp out in between waves.