Lots of things to consider here but the first thoughts are to relax and make sure you change only one variable at a time then look taste and tweak as required. Make several changes at a time will not help you improve as fast.
With the Kyocera I have it has the same stepped notches as your Hario but I find that normally this is not to much of a problem but I agree a smaller step would be nicer. Some different beans still take 2 clicks in or out compared to each other.
First question for you are you using the pressurised baskets on your 800 or have you thrown it in the bin where it belongs? Adjusting grind and Tamp pressure to some degree with pressurised baskets does nothing much to influence the shots. To fine a grind on a pressurised basket will just get messy and sloppy and still taste ordinary to course will still get you fake muck in a cup :P