Well in the end it comes down to how much hp you can afford, you could get 600hp out of it but the cost would be staggering. Any standalone will do it some some are more common than others. There are also piggyback solutions which would actually be not that bad for what you want. Over here we use link because it has a good userbase in NZ and its what I've got I'm just gathering the other things I need. The big names are Link, Microtech, Wolf, Megasquirt, Haltech actually I could go on for a while they can be a royal PITA to tune and to learn what you are doing but once you know what your doing you can do anything with them. It comes down to what you are familiar with or what you think you can learn, the best ecu is worthless if you can't use it or your tuner is not familiar with it. The best ecu is what you can use (or learn to use somehow)
Granted that you are asking this question I woudn't think you have a very broad knowledge of tuning engines so you may be better off with the 4agze ecu and some messing around with a Fuel Pressure Regulator or getting a piggyback for the 4agze ecu like the eManage which just tweaks the stock ecus fuel and spark or just a fuel computer since it is a stock boosted map. As long as you get it running reasonably well you can take it to a tuner and do a few dyno runs to get it a bit more finely adjusted. It has less flexibility but as long as you don't want to raise the rev limit and do some of the other trick things standalone can do it works well.
This is where being friends with a tuner would be awesome you could bum off him instead
