As Von Lucky et al said, don't wory too much, they do look good.
Another (slightly lengthier approach) to smoothing the colours out a bit is the use of filter washes. They're very dilute layers of wash that, possibly over several applications, smooth out colour transitions. It is possible to do this with acylics, but because they dry fast it's a much less forgiving medium, you don't get much time to manipulate the paint. Enamel washes like those produced by MIG Ammo or AK Interactive, despite being enamel based, I think are easier to use, though they do work better if the model's been given a coat of gloss or satin varnish first (a smooth suface lets the wash slip easily around the detail - matt paint has a fine granularity that tends to grab the pigment, creating 'tide marks'). It may require two-three coats (giving each at least a couple of hours to dry) before a final coat of matt varnish.
It's probably also a good idea to keep some turpentine (or the brands preferred thinner) to hand as it's good to experiment a little on a piece of scrap plastic in the colour you're trying to blend to get the right consistency - it being better to have to apply another coat than it be too heavy.
You can see how filters can smooth out colour transitions in the Centurion below - the first pick in the 'raw' green modulation & the second after two coats of Mig Dark Brown for Green filter.
Hope that it may be of some use!