I did take it that the 10m run that you mentioned is mainly horizontal pipework and if so this will be the reason why it's slow to heat up.
Two pumps not a problem.
I would put the pump on the primary flow and set it to the lowest speed.
Fit an air separator onto the expansion pipe and put the cold feed into it (this should resolve any pumping over issues)
For a really cheap wire up/contol you could plug the pump/cylinder stat set up into a plugged in time switch that's set to come on the same time as the boiler.
I've drawn a diagram of it and uploaded into my pictures so you can take a look at.
I can't see any problem with the system, although you won't find it in any plumbing manual - but for your specific needs it's just the job.
Two pumps not a problem.
I would put the pump on the primary flow and set it to the lowest speed.
Fit an air separator onto the expansion pipe and put the cold feed into it (this should resolve any pumping over issues)
For a really cheap wire up/contol you could plug the pump/cylinder stat set up into a plugged in time switch that's set to come on the same time as the boiler.
I've drawn a diagram of it and uploaded into my pictures so you can take a look at.
I can't see any problem with the system, although you won't find it in any plumbing manual - but for your specific needs it's just the job.