That lag is ridiculous for a TD04 on a 2.5L! The peak numbers are sound, but the idea of a TD04 is to punch it up nice and early.
I wouldn't worry about a boost figure as such. Let the tuner find the best combination of boost, fuel, timing etc etc etc. I would get a figure of boost and a copy of your baseline dyno result. Figures are great for wanking over on a forum, but you should use a dyno to look at where you are making gains.
i.e. this is off my evo. As you can see the baseline result was farked! (explains my lack of love for the car for a long time).
It also lets you see if the tune is worthwhile. I.e. you don't want to smash in 2 bar for a 10hp gain.
Hope you get it sorted.