I've been helping install and operate both the JRS and Self Employed equivalent as part of my work. It's been utterly exhausting - we've done it from our bedrooms, spare rooms, kitchens and living rooms, working form home at short notice after the lockdown. Luckily for me I am IT savvy, but a lot of us aren't, and have had to learn an awful lot about remote working in a short amount of time, as well as organising and planning these schemes at break neck speed.
The Self Employment Income Support Scheme is by far the more complex of the two, despite being of far less value than the JRS. It's still left an awful lot of people out of the equation, principally those who put their pay through their own limited company and pay themselves by dividends. It's far from perfect - the principle issue will be the aftermath, because they are inevitably going to make us pay for it all via increased taxes and NHS contributions. Problem is for public sector workers like myself, we've had 10 years of pay freezes and/or below inflation pay rises anyway since the 2008/09 financial crash - so we can look forward to 15 more years of austerity....