Paint, you lost me on that one, it will not do anything for you.
By adding weight I am not sure you will get any more control. Usually those types of things give you more depth, power or other things, I have never heard of it adding control. You can of course always tighten the string tension.
actually, weight will increase control. more weight equals more stability. if the incoming ball's momentum overwhelms your racquet (this is even more crucial when volleying, as there's little racquet head speed to speak of), it will be difficult to control and execute the stroke at the moment of contact; how you intend to make the stroke will be offset by the relatively high momentum of the ball. imagine using a fly swatter for tennis, you can generate all the racquet head speed you want, and with perfect technique; you won't get any power, let alone control! stability, hence, weight, is a pre-requisite for control; less weight will lead to more deflection/wobbling on impact, and the more uncertain your shot will be.
no wonder that control oriented player's racquets are almost always the heaviest you'll find. and on a more technical note, as far as i know, greater weight equals a larger sweetspot, which translates to more forgiving off-center shots, other things being equal.
having said that i don't think adding weight to your racquet is such a good idea. minor tweaking is okay, but anything greater will distort the architecture of your stick.
as for tension, again, not such a good idea IMO. compensating for control by increasing tension slightly is good, but anything greater and you'll have major side effects. change in spin generation, discomfort, feel, touch, shock to your arm, tennis elbow, irritating sound.....
a racquet is an object with complicated physical properties; adjusting one aspect heavily will be counter-productive and have unintended consequences.
my advice is to get a racquet with the proper attributes. period. first and foremost, if you want greater control, switch to a smaller head size. nothing else will benefit you more on net.
second, a heavier racquet (though usually smaller head sizes come with larger weights anyway).
if all else fails, increase string tension toward the upper recommended range.
if the heaviest racquet sold today is close to 360 grams and you believe you'll play better, with more control, with 400 grams, then you might want to consider adding lead tape!
oh, and i heard that blue racquets tend to have better control.