Those are looking great! I’d wait until you get the run finished before you think about changing too much
Are you using the full 3 part gh or running Lucas formula?
Something like that you def want to look at either rockwool or a coco/pearlite mix. Just top feed for ease. Getting around in those things is a nightmare. Just run trellis netting to make sure you can use every inch of canopy.
When it comes to the lighting I personally prefer hps but you have...
switching to rdwc and running a chiller is an option
Something like cleanse from Athena is probably your best bet. It’s just chlorine to keep any bacteria from building up