IMHO the base price will be kept similar to the old RS3, just under £40,000 base. The base A45 AMG is currently £38,200 and Audi seem to want to match or better that car with everything !
The base S3 is around £31,000.
The biggest change for me will be the new MQB chassis which should provide much better handling based on the current S3 and Golf R reviews. The reduced weight will also help. We'll have to wait for the road tests to confirm that though.
Looks wise it was always going be fairly similar to the existing A3 model IMHO.
I'm switching back to a new Golf R in March, but may well come back to the RS3 in two years ! I'm going to miss that 5-pot engine for sure.
The forums always seem to knock new models when they are first announced, mainly on the looks. But once they are out for a year or two opinions will be a lot different, especially if they are good to drive.