I can't answer all your questions, but I can answer some. You don't have to have four conditioners
Personally, I have 2. I use one for everything, and I use one for a deep treatment or the rinse out if my hair is feeling dry or if I feel like it needs it.
My one I use for everything is Suave Naturals. I don't use the coconut scent because I can't use it as a leave it. Protein overload. My deep treatment and rinse out when I need it is Tresemme Naturals Radiant Volume. I know you said you wanted to go natural, but I'm not sure how natural you want to go. I find the suave naturals is very light and doesn't weight down my hair (very easy to do).
My general routine is to cowash with the suave naturals mixed with a couple drops of tea tree oil, condition with either suave naturals or tresemme naturals (with coconut oil on some days), if I'm shaving I'll put a shower cap on to let the heat help it penetrate, do my shower thing, rinse out the conditioners. After that I rake my leave in through and then rake in a gel (I use Aussie Instant Freeze. Excellent gel and it doesn't weigh me down). I then use the super soaker method to promote clumps. Then I plop and air dry.
If it's CG approved, you can use it for anything. You could have one conditioner for all 4 things you can do with it! If that Hugo one is what works for you, go for it! I tend to use a TON of conditioner for my cowash so I prefer the cheap stuff so I don't feel guilty about using a bunch.
To start, use very little leave in and styling product. Only a little shouldn't leave you greasy and you can always add more if you need it. It's all about finding that balance.
Here's one thing I found early on: Don't use a super rich conditioner for your leave in. That made me overconditioned in just a couple uses. I had to switch to something lighter.