Thoughts on LN fees:
At an avg of 7261403 Satoshi channel one would pay ~3210 Satoshi in fees to empty it completely at an avg fee of 442 ppm. (7.261403 * 442 ~ 3211 OR 7261403 * (442/1000000) ~ 3211) but LN is said to be much more suited for smaller payments. (as described in 'river-lightning-report')
Still, an avg fee of 442 ppm seems quite affordable, ~500k sat payment would incur an ~221 sat fee, which is quite reasonable. It is as cheap or cheaper than some 1 sat/vbyte on-chain transactions (yes I know, 1 input 1 output is even cheaper on-chain but have you sent many of those?) calculate yourself at 
If we take the median & only use half of the channel (1 mil) we would only pay 30 Satoshi which seems hard to believe as the payment amount is over four times more than the avg (98.7% success rate) payment described in 'river-lightning-report' p. 15: https://river.com/learn/files/river-lightning-report.pdf
"our payment success rate in September is 98.7%, across thousands of daily
transactions, at an average transaction size of 230k satoshis (~$46), and a median transaction size of
24.4k sats (~$5)."
At the avg of 230k sat the avg fee would be ~97 sat & the median only ~7 sat.... At the median of 24.4k sat the avg fee would be ~11 sat & the median only ~0,8 sat.... I will repeat myself, the fees seem very reasonable & the lighting network does seem to provide cheaper fees than on-chain transactions. But that was a foregone conclusion. (From the lightning network whitepaper to that river-lightning-report)
Keep in mind, I did not take base fee into account as I believe it to be moot. At 7 hops, which I remember is the meme to reach everyone you would pay ~5.306 sat with the avg base fee. That's around 0.0218% (or 218 ppm) of the median 24.4k sat payment... I have a feeling small payments find routes with better success, still what you would pay is much in line what I have been repeating.
Now do the avg & median fee give a full picture? no, I imagine more research is needed. Gathering data for payments, seem like a stumbling block... Again I imagine node runners don't want to release these for privacy or business related reasons. I hope there is an effort to analyze successful payments, their amounts & fees.
TLDR: LN is ⚡&🆓
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