Since you have mentioned you want a powerful motorcycle, we would recommend you look at the Triumph Scrambler 400X, KTM 250 Adventure and TVS Apache RTX 300 in the ADV / Scrambler category. Of the three, the Triumph bike is the most powerful, but it is also pleasantly usable inside the city, whereas the KTM and TVS are more do-it-all machines that will also be wonderful on a day-to-day basis.
Coming to the Xpulse 421, there's no official communication from Hero on when it will be launched, so we would recommend going with any of the other options you are considering.
Take a test ride of whichever option you shortlist before you choose.

