NO you cant take it off keep the car the way it came out of the factory, you dont relise how difficult it will be to get the ELF sticker in 5 years time...
I have a really good friend who owns a Clio Williams 2 and the car is spot on, the only thing missing to make it look like new is the elf sticker in the back of the car, due to the different logos which they have had of the past 12 years.
When she spoke to Renault all they could get for her is the one on the Trophy now, which is not the right one for the Williams.
Therefore when it comes to keeping the car like new, I really would suggest keeping the sticker.
With regards to the plates, definaatly lose them, but keep them in the garage for when you sell the car, always looks good to a buyer if it has the orginal bits.
Personaly tho Stromba in most cases i think its just the fact that it was on when it left the factory and is still on ie in some peoples mind it makes it more oiginal