right now i think merge mine as many coins as possible with uno is likely a good approach. Especially the good ones. Miners like it, uno doesn't need a change, get more hash and it doesn't bloat the uno chain.
Are there any downsides to that?
BN has your answer:
And if Unobtanium 'nearly' has a sustainable mining rate, then it still doesn't have a sustainable mining rate.
True. If UNO goes to $1000/coin tomorrow then we must pay the miners, the POW network, $15,000/day. I think that is a bit much. But we will only have to pay $4000/day around November. BTC @ $1000/coin must pay $3.6M/day.
This makes UNO 900x more efficient at securing value on a SHA256 network. Does this sound appealing? And it gets more and more efficient as we approach year 2020.
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NOTE: once we reach the sustain mining rate of production then the dynamics change. For right now UNO is a 'Fair Distrubution' not a 'BTC side chain' kind of coin.-> If I'm understanding correctly, we like UNO to have a sustainable mining rate with predictable/gradual increases in hash (mining rate) pairing nicely with increase in value (affecting cost of mining) and PoW requirements (difficulty of mining). Sudden jumps in hash rates resulting from "as many coins as possible" merging with UNO could have a negative effect on UNO's efficiency as it demands more daily overhead, ultimately hurting our growth, price, security (attacks if they ever ramp up from <5MHash scrypt targets), agility, etc.
*Still learning here so the above may be baloney.