Actually Lightning could use any cryptocurrency in place of bitcoin. Or even multiple cryptocurrencies, with some (or all) nodes and hubs doubling as currency exhanges. That would let users choose the combination of speed, hashpower, and transaction fees that best suits their needs.
That would introduce security issues. There is no evidence that other cryptocurrencies could stand up to the same level of attacks Bitcoin has successfully withstood. If you are using LN, then you wouldn't benefit from the other altcoin transaction specifications anyway.
I don't think users - or anyone really - are capable of judging how secure any given cryptocurrency is relative to transaction cost, speed etc. It's a bit of a problem - ideally you'd like to see the market settle on an optimal security vs. cost ratio, but mostly users won't know security has dropped too low until something very bad happens. And if security drops low enough to really undermine the viability of a crypto, it's quite likely that coin will see a severe drop in valuation, leading to further drops in hashrate as miners go out of business.
I guess this would be a partial argument for why centralization of mining is inevitable, as only large miners with sufficient bankroll to survive bad patches will endure in the long run.