There are cheap-ish generic lens hoods. I have a couple and they work perfectly. I like them in part because I consider a hood to be an expendable accessory since they seem to take the brunt of the damage from minor bumps, scrapes against rocks, etc. So, I don't fret them much and if one of them gets cracked, just buy another cheap plastic generic hood. The Hasselblad hoods are also plastic, for the most part as well anyway. Also, I haven't done it yet, but I figure I could buy a longer hood and cut it down for certain purposes quite easily since the are all basically B50 or B60 sized, so very interchangeable.
Finders are (I think) basically crack narcotics to a Hasselblad shooter. You have one, but discover that under certain circumstances, it isn't ideal... so you buy another, and another. Add in metering options and vintages, etc., and there are a lot to choose between. However, if you are thoughtful and observant when you shoot, you could probably minimize the number you own to keep it to a minimum. I own a folding waist level finder mostly for when I really want to travel light with a body. It doesn't get used much. I own the most recent metered 90-degree hood PM90E as my primary shooter. It's much, much larger than the WL finder, but it has a meter and the image presented is, frankly, far better than from the WL finder. Also it has built-in diopters, which is important... lastly, I have an modern unmetered 45-degree hood PM45, with the diopter built in. Since I got the metered hood, I don't use that one much. You'll never find the diopter you need, so IMO, buying a finder with a variable one is the only way to go (PM45, PM45E, PM90, PM90E).
The focus screen choice is an additional problem for expense. There's tradeoffs between focusing and corner falloff, and it's hard to know which one you are going to like or want without trying several (at least of the different vintages, from the oldest, to the newer (Acute Matte and Acute Matte D, which are very expensive). Plus the variable of microprism area, split screen, aerial image versions, I consider the aerial image ones to be somewhat special purpose, etc.). On top of that, there's the grid lines that may be selected.
I settled on the AM-D grid screens for my bodies. I used to shoot LF with gg that had gridded screens and I prefer that. That locks me into only one or two options; whether to choose AM or AM-D.
Note that there is additional complexity associated with the metering interaction between a metering VF and the ground glass... the documentation for the VFs shows which ones are directly compatible and what their adjustment is, depending on the vintage of focus screen.
It's a minefield of interactions and expenses, but I do enjoy shooting with the system. But for absolute simplicity, I'll take a Mamiya 6 camera and lenses any day. Far more limitations, but what a great light travel camera.