Reference to MoTs, fines, etc..
If asked to stop by a Police Officer or PCSO cyclists are required to stop under law. An Officer has the right to inspect your bike to assess its road-worthyness, or have someone assess it for them. IIRC you can even be fined for having no brakes, or any other defect.
On speeding..
You can be fined or prosecuted for wreckless cycling or wanton and furious if the situation is seen as a danger to others. This has been done a couple of times, though keeping up with cars in a 40 zone wont usually count. Cyclists can have the same obsessions with speed that motorists sometimes have
Insurance..
Household Policies, union or club memberships often have some cover that will help. However, even if you dont have those you're less likely to act like a c*ck on a bike for the simple reason that any collision you cause will most probably hurt you more, even collisions with peds can result in the cyclist coming off and biting dirt. Many of the people who bitch about this often do so because they see insurance as some kind of garanteed windfall: "I've been hit, now I'll get some money in damages!" Its part of the rise in NoWinNoFee companies ad the litigation culture that has sprung in the last 10 years.
Licensing and reg..
Daft ideas for bikes. Pretty much every system around the world that has been in place has been a massive administative headache for the authorities. Set the fee's too high, or make the system too complex and people just resort to cars and dont bother with bikes. The Toronto investigation into a proposed system found that they would have to set the fees at well under the admin costs and that they would lose a fortune. People were surveyed and they all said they would be in the main unhappy with doing it in the first place and at having to pay anything over a couple of dollars a year (this was in the 90s).
A similar problem had arisen in the UK in the 80s. IIRC Thatcher was responsible for scrapping the dog licence as it had been costing the government a small fortune, and those staff that dealt with the set up were needed elsewhere.
Plates will cause problems for two reasons - 1. they will be too small to be read via CCTV and automated plate systems (ANPR). 2. If a driver has a grievance with said cyclist they may well try and drive too close so as to read said plate. 3. Anything too large will cause drag. 4. The sign will have to be positioned so as to be away from moving body parts - this means away from the legs, and in so doing it needs either a rack or an adapter to be fitted. 5. if operated at night this will need additional lighting so the plate is visible
....I think we have to see cycling (as well as walking) as free. We need to keep it that way or else it just overly complicates peoples lives, government operations and would cost us all in the end. We have major problems in the UK with obesity, mental health, traffic congestion, road surface issues, the environment (carbon monoxides, dioxides, particles of soot and chemical compounds, as well as substantial noise is all released when you turn the key)...
...cycling to me, as with walking, seems to be a valid aid to dealing with this.