Someone in my office showed me these things last year and I’ve been thinking about them for awhile. Here is versions 1, 2 and 3. 3 finally is spinning, but slowly. Any advise would be GREALY appreciated.
Here’s link to spinning:
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If it’s spinning too slowly you have three major ways to speed it up.
Increase the force, aka add more candles. This is a bit problematic due to fire risk. Use caution.
Reduce friction. You could make or use premade bearings to make the rotation much smoother. You could use a wax to make the points that do rub slipperier. Sanding the dowel smooth might help. Sharpening the end of the dowel where it contacts the bottom might help.
Reduce mass of the blades. Rotational inertia and momentum are increased with extra mass. Use a thinner material (1/16” non PG hardwood maybe?) to make your entire assembly less massive. Bonus: this will reduce friction too. Caution: thinner material is likely to have lower thermal mass, and has greater surface to volume ratio so the risk of fire will go up.
Also:
Changing shape of the blades might also reduce the mass without losing much rotational power. They can be thinner at their base where not as much heat is reaching them.
More thinner blades will give you a more consistent rotational force.
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The candles to blade distance is far greater that the working examples we had years ago. I understand the need to be safe but think they could be a little higher. The easiest improvement might be to use a bearing. Pick them up at a H/W store like Tru Value or someplace. Or if you can find an old pair of inline skates (nobody does that anymore) you can salvage the bearings.
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There is a glass concave piece inserted in the wood (link at bottom) and a small wood screw through the bottom into the glass piece for least amount of friction. I thought about scotch tape on the wood for friction at the top, but didn’t like the look. Sanding is a good point 
but maybe that is version 3.1 I don’t have 1/16" PG. I may have to get some. Great Idea! all the rest is draft board right now, as this was testing version.
Changing shape of blades? I may have to play with that. I’m not as worried about mass/weight with the small amount of friction of screw tip on glass, but every bit counts.
THANK YOU for the advise. Truly appreciate it.
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Distance from candle to blades is about 6 inches. Not sure you can tell from picture. In versions 1 and 2 it was about 9 inches.
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That looks about perfect speed to me. They’re not meant to spin fast.
That said, they are generally designed to be hung from the top on a bearing like you are using, no contact at the bottom. A pillar coming up thru the middle with the bearing on top.
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Agreewith @eflyguy - speed is fine. I think this is a wonderful version of the classic - well done! 
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I agree also, the speed is fine. Love it!
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Wow this is wonderful! I tasked my students with creating one of these as our STEM project in German class. The way you attached the paddles to the top is a great idea. None of my class had thought of that yet. They were stuck on that part - how to print something with the Glowforge that would hold the paddles and move. @GlowWorm , would you be able to share or sell the design you used for the top? 
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I will look, but changing computers and not sure where file is at the moment. HOWEVER :). this one is much better than mine: Pirates of the Caribbean German candle pyramid plans
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found it quicker then I thought. free to use, do not sell, no license transfer, blah blah blah.
Small Christmas Pyramid.v4.ai (299.8 KB)
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For the record, it’s spinning faster than mine. (And your blade-angle solution is elegant… whereas mine was an old TinkerToy.)
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….now I miss my old tinker toys and constructs toys.
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No idea how I missed this thread for 2 years…
I sell pyramids like these made on my GF and have a couple of suggestions. As mentioned above, the blades are a LOT of mass for the convective air current to push around. Using 1/32 or 1/16 basswood or balsa will allow a much more effective energy transfer. Taking that idea further, anything you can do to reduce the mass of the carrousel will improve the motion. I use a thin brass rod as the center axle, sharpened into a point that spins on the exact same glass cup bearing you used in the base. Hope this helps!
Note the thin blades and brass axle.
On the other hand, this one has blades from 1/8 proofgrade inserted into a three-layer hub (tinkertoy analog, file at bottom 
) and spins great on the brass point:
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