Congrats on the Marrakesh!

Regarding dynamos:
Schmidt SON are the acknowledged best, and most expensive.
Shimano offers many dynamos at different price levels, but even their best (-80 series) are considered not as good as a SON (a touch more drag, etc).
SP is a newer manufacturer (5 years, maybe?), and their dynamos are considered better and lighter than Shimanos at a nice low price.

I have two Shimano dynamos (DH-3N80 and a DH-T780), and they work great. They can be found for excellent prices from European bike websites; I paid less than $70 for the 3N80 and $175 for a complete T780 wheelset.
I also have a SP PD-8 wheel that I found used, and it works great as well.
I can't feel any difference in performance between the Shimano and SP dynamo hubs.

For lights, more lux means a brighter light, but some lights have better or worse beam patterns. I've bought all my lights from the German bike shop websites for great prices.

Here's some more reading on dynamos and lights:
Lighting systems
https://momentummag.com/what-you-nee...namo-lighting/
https://swhs.home.xs4all.nl/fiets/te.../index_en.html
https://www.bikelightdatabase.com/be...%5D=vis360plus


Regarding panniers:
I've tried a couple and my favorites are Ortliebs, because they're waterproof and their attachment system is very, very easy to use. Again, best deals are found overseas, but they do come on sale on REI and other US stores from time to time.