Something to think about -
The way BitCoin was designed, miners are very important part of the security. The more miners we have, the higher the hash rate. The higher the hash rate, the more expensive (and thus difficult) it is for a nefarious interest to pull off a 51% attack.
With off the chain transactions, miners lose their incentive to mine. It costs them real money to mine.
As they lose their incentive to mine, the relative hash rate decreases. Miners leave mining rather than update to modern technology because the profit is no longer there.
With a lower hash rate, the ability for a nefarious interest to pull off a 51% attack becomes less and less expensive and the security of the Bitcoin network is reduced.
Miners are very important.
Agree. That is why I think that Lightning Network's off-chain transactions will pose a higher security risk for Bitcoin as miners will lose the incentive they use to earn by finding blocks. However, I think that now, miners are earning more Bitcoin because of the increasing transaction fees.
The way I see it, miners would find the most profitable way for them to find blocks, thus making most of them to accept Bitcoin Unlimited soon, since the same doesn't have a fixed block size limit, allowing miners to set their own preferred size and earn more Bitcoin out of it.
Still, Bitcoin's future is uncertain and while it is the most secure cryptocurrency in the world right now, it could be subject to change if a bad decision is made within the consensus of miners and development team as well.
Nevertheless, I'm looking forward for Bitcoin to put an end of its slow transaction confirmations finally, and become great again to serve its purpose for everyday transactions. Just my thoughts.