You should take the Pipercross kit into consideration, it is cheaper than the J1, I recently installed it on my Fiesta, great quality and noticeable improvement both in sound and throttle response, although it takes a little bit more time to install....
I will upload a short video to show how it sounds....
Car looks very nice , your doing some good additions. No so sure you will be able to fit the Ecoboost Engine in there , without most of the wiring loom and modules and power train , i would imagine it would be a very large project to undertake such a task. But if you manage it post a fitting guide i'm sure people would like to see how it turns out.
I know it could be a large project, but where is the fun if it all just bolts on? The only thing that worries me is the electronics, but I have a friend who could make it work
EDIT: I was thinking of a 148 bhp 1.6 ecoboost swap, because it has enough power,and does not require complicated power train modifications
not much you could do really,i have a 1.25 in my mk7 fiesta,went to see what SKN tuning.de had to offer: +14 bhp and +15nM,not bad for a N/A engine,they also give full warranty for the performance gain (still believe that the increase isnt that much,probably around 8-10)
so that is the first thing that i will do after my warranty expires,than probably a full miltek exhaust etc.
hint: took the car on the dyno run: it puts out 86 bhp (if i remember correctly) instead of 82 bhp ; also it is a standard car,no engine tuning yet