Some say it really is important ''getting it to run right'' as a starting point before doing any mods, especially paying attention to maf sensor and get it sorted by either cleaning or fitting a new one or give it a try with mafam or combining it with a pierburg maf.
When you get satisfactory results and your derv shows some real muscle immediately from 1k then you should proceed with the planned mods and eventually a remap. Otherwise you may learn the hard way a properly running oe spec car is accelerating better than a 150+ bhp tuned one...
No matter how many horses are there if they are tripping each other on the way