I think new tyres always feel lighter than the old ones. I'd say normally it's because A. They are at the correct pressure. B. You have full tread depth so there is probably a fraction less rubber on the road itself.
Honestly, if the tyres are at the correct pressure and the car isn't doing anything silly I think you'll get used to it.
I do about 40,000kms per year so go through tyres about every 18 months I guess. I love the feel of new tyres. It's like the power steering got a boost.