I recently test drove the 570 and it was peppy and fun to drive but no more so than my 12C. And it didn't feel particularly exotic to me in terms of interior styling or features.
I don't think the point of the 570S is to feel exotic. It's a luxury sports car and on those fronts it totally succeeds. It feels very luxurious and comfortable inside and it drives beautifully both on road and track. Like your 12C it's wicked fast when you push it but completely sedate and comfortable when you want it to be. To me it hits its goals perfectly and I absolutely love the car. Despite having the three other McLarens (and a Ferrari and a few other cars) I feel very drawn to driving the 570S on a regular basis. It just has such a great right feel to it. To me that's where McLaren is really hitting the nail on the head these days. I had two 12C Spiders and they were wonderful cars but the 650S Spider had a better "feel" to it. Then the P1 came along, again with more "feel" and now the 675LT which blends the right amount of P1 feel and the right amount of 650S feel - I'd say 85% 650S, 15% P1 which feels like exactly the right mix. The 570S also has that incredible "feel" that makes it so wonderful. It comes from steering, brakes, engine & chassis - the ingredients have been there from the start of the 12C but they seem to be perfecting more and more with each new model.
Because of that, I'm looking to get a Lambo Huracan next. I wanted something totally different than the 12C or the McLaren family. Huracan is v10, naturally aspirated, all wheel drive, with styling I like, and a high tech cockpit. Plus the sound of that crackling Lambo engine. Really a totally different experience than the 12C or 570. I'm also in the market for Ferrari 458/488 but I think I want the Lambo more.
The 458 will fill like a bit letdown after your 12C. It's a great car but I had a 458 Spider and once my 650S Spider arrived the Ferrari only got pity drives so I sold it. The 488 should be in the same performance class as the 12C/650S, so it will likely be a more compelling car than the 458, but the chassis will be a letdown after driving a McLaren. I've not driven a Huracan but I'm guessing it will be a similar story.
And interestingly, I have the McLaren in Blue, will get the Lambo in white and I would want the Ferrari in classic rossa corsa red. I like MarkNC's red, white, blue cars too.
Volcano Orange, white and blue actually
If I were you I'd skip the Ferrari and Lamborghini and get in line for the McLaren P14. I'm pretty sure, based on McLaren's track record that I described above, that you will thank me for this advice after you get the car. But if cars are your hobby and you don't mind spending the money it is nice to have different experiences to figure out what suits you best. I still love my Ferrari FF and plan to upgrade it to the GTC4 Lusso this year.
Variety is the spice, at least for me.
If you have the appetite and the time then there's nothing wrong with trying everything on the menu! Enjoy!