EVE New Citizens Q&A

Sorry for that. If anyone is feeling generous today, I hope I can get some good advice :)

My situation: Work Mon-Fri and on the weekends. At work I can remote in and do the occasional update. On the weekends I have some more time, but need to be able to jump up at a moment's notice and be gone for 5-20 minutes.

I quite like mining and want to build up some cash and train some skills before venturing out and trying other things.

I started out by mining Plagiolcase in some 0.7s and 0.6s with a Retriever.

Currently I'm using two accounts, both with a Porpoise, to semi-AFK mine 0.9 Asteroid Belts.
Point being, the Retriever's hold is too tiny, two Porps iss easy to set up, I can be away for some time, and I can check in fairly reguarly to see if all is well and I need some new 'roids to sick my drones on.

Question:
I'm sorely tempted to try an Orca (cargo space, and tank-y) and another more high-yield ship for just that, a slightly higher yield and an easier way to go from mining Veldspar in 0.9, to, for example, Plagioclase in 0.6.

From what I've read on here an Orca is probably somewhat overkill, but I just like it's health and space for ore (less hauling).

I've been trying to wrap my head around the different ships; Covetor, Mackinaw, etc.

What would be a good second ship that's not too soft on the armor and good at stripping that ore from those asteroid?

Bonus question: if rats come into a belt, will they always attack the "weaker" ship? E.g. if I were to venture into a 0.6 belt with a Orca and a Retriever, will they always go for the Retriever?

If you got this far, thanks so much for reading.

To your specific questions:

1. Originally, the different mining ships offered choices between mining yield, ore hold, and tanky. One had 3 strip miners, one had a larger ore hold, and one was tankier. Then CCP changed their minds and decided to give them specializations, one for ore, one for ice, and one tanky. Then they changed their minds again and I don't know WTF they did; all of them have 2 strip miners now and I haven't bothered to look at the bonuses. But when you compare mining barges, basically you're looking at the bonuses (ore? ice? gas?) vs. ore hold vs. tank. And the tank often depends on the amount of powergrid the ship has available, to install oversized shield extenders and resistances.

2. I've seen rats switch between my Venture and some guy's mining barge, back and forth, so I'm not sure what they'll do. Typically, high-sec rats aren't a threat, especially if you leave out some combat drones and set them on aggressive. If the drones are already deployed at the moment of attack (and they're set to aggressive), they'll automatically shoot back at the rats and kill them.

3. The Orca may be tanky, but if you're semi-afk, CODE et. al will have plenty of time to scout out your location and fittings, and bring sufficient firepower to take you out. Esp. if you go to the lower high-sec. I mean, they're organized enough to bump and take out freighters in high-sec, Orca won't be that big a deal.

As far as the barges go, there are three of them.
The Procurer, the Retriever, and the Coveter (small, medium, large.. well sort of). All three use two strip miners (in ages past is was 1,2,3)
The Procurer has a base of 16,500HP, the Retriever has a base of 6000HP, and the Coveter has a base of 3500hp (about as much protection as the tin foil around a baked potato)
As far as drones go, the all have 25mb it of bandwidth (so 5 lights or mining drones). The Procurer and Coveter can each carry ten drones (so you could do 5 lights and five miners. The Retriever can only carry five, so you’ll want lights to rats unless you have another ship covering.
Next up is the Ore Hold. The Procurer gets 12,000m3, the Retriever gets 22,0000m3, and the Coveter gets 7000m3.
ROLES: Here is where the differences are
Procurer gets a bonus to cycle time of strip miners (which means they mine faster, but not more material) and Shield HP per level of Mining Barge skill. The ship also gives a 50% bonus to drone damage and hit points.

Retriever get bonus to its ore hold storage space and faster mining rates (same rate bonus at Procurer) per level of Mining Barge skill.

Coveter get a range bonus to its Strip Miners as well as the same mining speed bonus as the other two ships per level of Mining Barge skill. It also gets an additional 25% flat bonus to mining cycle times and strip miner activation costs.

TLDR:
Procurer is a tanky ship that can defend itself well and has an OK ore hold.
Retriever is a lightly defended ship that has a very large ore hold and can hang out in the belt for a while before it gets full.
Coveter is a thinly armored ship with a 25% faster mining rate, but a very small hold that will require being emptied about every three cycles of the strip miners.