Some nice stuff you have there. I would go, in order of priority:
1) A refractometer to measures salinity. The tool you have is very poor for measuring this accurately. Cost: $50ish
2) Some better test kits. Not essential during the cycle but you will need them sooner or later. Salifert for Calcium, Alkalinity and Magnesium ($50ish for those three) and a Hanna Egg for Phosphates ($60 alone but you will get your money's worth over time)
3) A media reactor to run some phosphate media. The TLF150 is always a popular starter, cost $70ish.
4) Some granular activated carbon in a media bag. Cost $notmuch
Otherwise you should be okay for a little while. You can always look at upgrades, but what you have should be good for now.