Welcome,
Skimmer, I have one, and I do like it, even if the new cone skimmers are the ones in fashion.
Salt choice, again not a lot of reefers like them. But I use it now for over a year. In the beginning it did not really make 1.025 on the mix as suggested, always too low. Now I found it gives consistent 1.025.
I see you bought an overflow box. Well it is still early days and I would suggest to rather have the tank drilled and an overflow box fitted. Although the overflow boxes like that do work, they are not 100% fail safe. But still your choice.
And enjoy the ride.