While ground condition are perfect now it is just a little too early to sow any of the game crops and wildflowers yet. You might get away with it but if the weather turns wet and cold in the next 2 weeks the seeds will only perish in the ground. It is very early in the year yet so I would advise waiting until the middle of April and hopefully conditions will be as good then. You should also have warmer nights from then on so the crop will grow faster with the higher temperatures by night. Even if it does go into early May before sowing you will be still in time to have a very good crop.
The only bit of Wildflower meadow maintenance that you need do for the year needs to be done now on the first available dry day.
Your plot probably looks very untidy now after the winter with lots of old dead stem and stalks and maybe some unwanted grass and weeds. Gather up all the dead trash and take it off the plot and as you do, give the soil a light raking to freshen it up and this will also allow the seeds that fell during the autumn and winter to germinate over the next few weeks . If any grass, docks, nettles or thistles are present take them out as well . Only do about half of the plot because you want to leave some of perennial flowers that are still there to flower. Do the plot in rows or strips of just in any random way you wish. Then sit back, wait and enjoy your rewards for the rest of the year. This time next year do the other half in the same way.