Some personal opinions and observations. I really like number 6. And it could be further enhanced. In its current form outsider will only see some perspective stripes, runway, speed, but the H-letter could stand out more. I think with a little tweaking, maybe filleting few corners of the rectangles to make H stand out, the whole design could raise to the next level. I.e. needs some further shaping.

Unfortunately number 3 does not represent H in the first sight for me at all. It's more like a random flamy figure, could be gas/oilcompany or bikers club or something like that rather tha H and crypto. Just my opinions.

btw two newbies on this very topic with 1 post 

Right - maybe we could work on that III + H themed icon still during the next 24 hours (other, new suggestions are welcome too).

Notice there is supposed to be the text "Heuristically Enhanced Asynchronous Transactions" in Nordic Rune Font on the sideline of my bad quality draft. It could be expanded to encircle the full round, and of course needs further stylishing (possibly more modern than the ancient style).

I need to state something here from a professional perspective. Yes I work on visual stuff daily basis. There are some adequate designs here and some amateurish. Now unfortunatelly those "III" (especially with out of date serif-font, rune etc) ideas fall on the amateurish side even just because it might be a nice idea to start with but evidently will not work on a contemporary logo-design. I just hope those who decide on this would take in consideration the fact that a good logo design is indeed not a matter of one's personal taste. If you would want to serve the business side of this i.e. create the best possible public image for HEAT you should ask a couple of professional outsiders how to go about this and I can assure you the outcome would be very different from amateur decision.

Com'on, see the original idea from 2 of your designs?

http://www.letterlogos.com/letter-h-logos/h-logo7.gif

http://www.letterlogos.com/letter-h-logos/h-logo5.gif

I'm not going to argue with you guys, may be best design win. Good luck all of you

Those do remind some other user's designs here. But if you look back in this thread and do your homework you have to admit my gvans-designs have nothing in common with those two logos you just posted.

And why would anyone smite me anyways 

edit:...and another one..this guy is just stealing other peoples work:

lol, did not even bother to change the color 

edit: check the comparison table from 1st page 

Triangular shapes work well on polyscapes too

HWiz funky designs, maybe try them out in 16x16 pixels size too so you will see how they would display at coinmarketcap.com.
I think you may have to scale up the actual symbol/letter part of the logo to make it work.

Great! Shall we just post the proposals here on this thread and at any time during the competition?

edit: added comparison table of current designs, pure monotone graphic form