I've done most of this on mine. To up the boost I have used a Turbotech manual boost controller that uses the spring loaded ball - very simply it stops the boost from getting to the wastegate until the boost gets up to the level that you want it at. So it won't bring boost on any sooner, or create more boost at lower revs, it simply lets the boost pressure build higher before passing through to the wastegate actuator where it bleeds off. Mine is set at around 14psi.
Regarding turning the fuel up - on a diesel you can't just turn up the fuel and assume that the excess will return to the tank. What happens long before the excess is returned, is that the engine tries to burn the diesel, and if there isn't enough air (boost) it generates heat instead of power - this is bad for any diesel, but especially risky on a 1kz-te.
If you are going to play with fuel and/or boost, you really should fit both a boost gauge as well as an egt gauge (this will change how you drive!!). The egt gauge should go pre-turbo if you can, but post turbo will do (you just have to allow for a 100-150C temp drop) - mine is post turbo in the dump pipe which is much easier to do.