Sounds like oyu guys are geting good deals offered. The style pack is pretty much a permanent freebie for the ST2. The £500 discount from Ford credit is when you take a loan of £2k+ and keep it for at least 3 months.
To find a car ready built will be your biggest problem especially in the colour/spec you want. The depends on the garage being willing to release it to your dealer.Otherwise you will have about 3 month wait for build/delivery.
I maxed my part ex on my 2013 ZS up to a handful of quid less than £10k so was well pleased (dealer is now selling for £10495), this was easiest way for me to reduce overall cost with my dealer, mind you mine is a smallish family business rather than a national dealership. Have got further deals on servicing etc so I was happy.
Disappointing if the power start is now optional, I got that included nice little extra. Didn't get the keyless entry/powerfold mirrors in the end cause it was too late by time I asked for them but not that bothered. Lots of folks on here have serious reservations about the keyless.
Good luck with your purchaes guys and keep us informed, you will not be disappointed when you get the car they are awesome.