Dragon is hyped up by Akainu, Doflamingo, Hancock, Ivankov, Smoker, Nami, Helmeppo etc. He is most definitely amongst the elite of the elite, the small group consisting of Dragon - Akainu - Mihawk - Shanks - Kaido just above the next group with Big Mom - Kizaru - Aokiji - Fujitora.
Sabo has amazing potential. He started out without a DF and thus had to become incredibly strong physically and with his haki as seen against Burgess, Bastille and crushing the Colosseum floor. YC1 without the incredibly mera mera that is underrated because of the magma fruit, mera mera is a yonko or admiral calibre fruit. With a bit of fights and exposure and haki bloom he is destined for the top.
Add in Ivankov who should be comparable to Jinbei and above Sanji pre-wano boosts, Morley, Karasu and the rest.