#2
You are going to have a hard time finding a quality kit for 320 euro. If you can save a little more, even 500 euro will get you something better. You don't start getting mesh heads until 900-1000 euro.
You can learn ok on rubber heads, but the feel is all wrong most of the time. Maybe if you can find a second hand or used Roland, you will do OK.
Any electric kit should take a double pedal, as long as the kick pad is big enough, and there's no reason not to get one if you have the money.

The drums can be made to sound like anything. The pads are just pads, they aren't anything specific until you set them up to be.
Harmony: Stratocaster
Alvarez: F-200
Schecter: Omen 6
Fender: BXR-60
Dean: Metalman Z Bass (Betty)
Egnator: Tweaker 15
Pearl: Maximum
ESP/LTD: EXP-300
Custom: Harley Quinn Bass
Custom: TK-421 Explorer
A steadily growing supply of pedals
#3
1. With that budget +1 on a used Roland kit. Only thing is though at that price range I don't believe they come with a kick pad for the bass drum but rather triggers.
2. Nothing wrong with starting with a double bass pedal.
3. It's an electronic kit so yes you'll be able to change the sounds on the pads for different cymbals, snares,etc.
ESP E-II Horizon FR
Gibson Flying V HET SET
ESP Eclipse II FM JB/Jazz
ESP M-II Deluxe EMG 81/SA
Marshall JCM2000 DSL/ JCM800 1960a cab
Tama Drums/ Sabian