Hi there Bluejay!

If you check out the later stages of my Messines diorama in the Figures and Diorama section you'll see my 1/72 scale figures and how I painted them. I also use acrylic paints, Vallejo have become my favourites now, originally I used Humbrol acrylics when they were virtually the only ones out there!
If you are painting the figures for a diorama and they won't be handled afterwards then you shouldn't need to bother with any varnishes on the figures themselves, wargame figures on the other hand are usually protected with a varnish (usually matt but sometimes gloss) simply to protect the paint from being worn away by repeated handling.
Larger scale figures can sometimes benefit from satin or gloss varnish on certain wooden, leather or metal items like wooden stocks or leather straps etc just to accentuate their textures being different from the cloth of the uniforms but in 1/72 scale there's no need for any of that.
As far as 1/72 scale vehicles and decals, the decals will adhere better to the models if they are first given a gloss finish (even though they're supposed to be matt), then use one of the decal solutions like Decalfix by Humbrol which softens the decals more than just plain water so they follow the shape of the vehicle better, especially if they are applied over rivets etc. You can either use a gloss varnish or (if you can get it) use Pledge "Multi-Surface Wax" (formally known as Johnson's Klear). This will give a good surface to apply the decals to and once they are dry you can return the vehicle to a matt finish with a matt varnish by brush or airbrush ( a cheapie one is fine for that!)
As far as the Mr Hobby's Paint Washes, I've never used that brand but I've used Citadel Ink washes which are water based. I would think that they would go better without any clear coat on the figures (I just apply the washes straight onto the acrylic paint). As for the vehicles, I'd use the wash after the matt varnish used to seal the decals on myself as you would want the wash to 'dirty' everything including the vehicle markings.
Hope you get on well and post up some pics for us all soon!

Robin.

I checked that mr. hobbys wash is oil-based, but it is a bit thick and heavy. Can I mix it with Tamiya acrylic or enamel thinners?

Also, what is the difference between the three varnishes? I can't seem to find an absolute answer online.

Thanks!

Hi again,
I recently bought a new matt varnish. Should I apply this all over my tank before adding washes on the vehicles? I read online that they advise a gloss varnish before adding washes, is the matt varnish fine as well?

Thanks.

Thanks!