Then it's high time to pick a standard and run with it. If 20 or so bigger distributors got on the phone and agreed enough is enough, your life could be easier. Get on the forums, and contact more and more dealers. Invite dealers in from here and across the ponds. The more dealers that demand, the faster it happens. Less grief for you distributers, less grief for the installers, and most importantly less grief for the people who pay everyone's wages and profit, the end user. The market does demand a few standards in this industry. Considering how high tech solar related has become, it is in the dark ages in many ways. Less need for trouble shooting and engineering after the fact will make life easier. I'm sure there are other things that need to tighten up that most, other then the engineers don't have a clue about.
There are many more who want solar then are buying it. One reason is finding no standards, and a whole lot of info that is written by electrical engineers for electrical engineers.
Even small things like the max PV isc per mppt can become a complicated, and hugely time consuming, research and Q&A thing for the non solar savvy crowd. I have a gsl 7.6k. I opened the box and pulled out the manual thinking all my information would be contained. What a joke. I couldn't find any panels that I could s and p to get a decent configuration. Most panels are around 11a. If I parallel I'm over the 18a max of the mppt. I read that these things can self limit, but nothing about how much, and the max panel Isc in the manual, or the the spec sheet. I asked here to no avail, I emailed the manufacturer more than once, and their contact people have no clue about their product in some ways. They told me the panels can't go over the 18A ISC. (Oh? Ok, I'll just run another $5k worth of wire the 250' that I need from panels, to inverter) Thankfully a member here who is electrical solar savvy with the same inverter sent me a PM. That crucial info is only found on a label on the unit. "Why was I so stupid as to think that the manual would have that crucial information" Nothing in the book, or spec sheet, and the factory reps had no clue. Again I say what a joke. The max panel Isc is 25a. I spent 12 hours +- of my time to get a small but very important bit of info, that should be plastered into every bit of literature.
I'm just trying to point out that not everyone is electrical savvy. That doesn't mean that those who are not as stubborn as me should abandon the idea of solar power if they can't afford an electrical engineer to design every detail for them, yet it is happening by the thousands every day.
There is no reason for a laymen to have to spend countless hours on a computer to find out if battery x will work with inverter y. Again stone ages comes to mind.