my suggestion is, take your time and just walk it, using a hand crank bag spreader
its what I do, been planting food plots for 30+ yrs, and used to average 16 acres every yr of them !@
yes iot sucks to walk, but its NOT that bad and gets you the better results, , unless you have a very good seeder, this will be your best option!
as the problem when you use a tow behind spreader with fine seeds is , like you said they come out too fast and you will ruin short, adding a FILLER to things won't help you, as if the filler is heavier it will fall to the bottom of hopper with all the bouncing of things as you tow it around!
and you will be seeding at mixed uneven rates
if filler is larger, then it will either clog up at opening and or need to be larger, which again isn't helping you get a good even coating!
Clover seeds are small and rather costly, si, again, if you want the best results, walk it with a hand crank bag spreader set at recommended setting for it or slightly SMALLER and then you should NOT run out
any lighter spots after a few days /things growing
you will see any missed spots or poor takes, and can go back and hit again with any remaining seeds!
another option for you MAYBE< is if your in a high farm area, try asking some local farmers if they have a proper seeder and are willing to seed for you, most farmers if they have the time will do the work for a few bucks and get you the best results, which could be worth the costs, 3 acres isn;t much time for them to do and shouldn;t cost much!
so food for thought for you maybe!