The bike is very nearly balanced on the centre stand - it takes very little effort to lift the front wheel. But if removing the wheel, you need something to stop the front wheel from going down. Axle stands under an inserted axle are ok, but I find them very easy to knock - especially since there is not much weight on them.
@Oldbikefixr 's suggestion of an axle stand at each side is better. I found that supporting under the sump was best - but make sure you have something to spread the load so that it is the sidewalls of the crankcase that take the weight - not the sump plate iteself, and what I had available wasn't particuarly stable.
But the best solution for me has been this little device

It is a Draper 450Kg Motorcycle Scissor jack, although I assume other companies make them. Only 8.4 cm high when collpased. Its just a tad longer and wider than the sump. It slides under the sump sideways - ie its long side across the width of the sump, which leaves the sump drain bolt clear. The bike is rock steady on the centre stand and supported under the sump with this. You're in the UK -
Machine Mart have them. SIgn up on line, if you can wait, then wait until they have a VAT free sale - it makes it a lot cheaper.
I use it on the floor, and on the bike ramp. The ramp can be raised and lowered supported like this - the bike remains rock steady. It enables me to get both wheels off at the same time and was a godsend when I took the front forks off.