What would be the benefits of 10x the energy spent Let's suppose the bitcoin network grew to be 10x the size it currently is in terms of the amount of energy spent. No other changes to the protocol were made.

What benefits would this have versus where the network stands today from an end-user perspective? If blocktimes are fixed at 10 minutes and blocksizes stay consistent, then what type of improvements would we see? 

Improvements


More Secure from 51% attacks
?


It seems confirmations could be sped up, but the initial confirmation still takes 10 minutes by design. I haven't heard of people complain about confirmation times, and from what I have seen on computing power performing a 51% attack on the bitcoin network as it stands today is not close to being practical. I am interested though what else I am missing.

I am not suggesting the use of POS or something else.
Note first of all that "10x the nodes" and "10x the mining energy" are different things.  A "node" is just a computer that participates in the Bitcoin network by receiving and relaying transactions.  Most nodes don't do any mining, but conversely a single node may support an unlimited amount of mining power.  So there is no real relationship between the number of nodes and the amount of mining power on the network.

Having 10x as many nodes would make it slightly easier for a user to connect to a node to send and receive transactions, and would make the network somewhat more robust against a network split (where not all nodes are able to communicate with each other).  However, it might also make it take slightly longer for a transaction to get to a miner, since more hops would be needed.  There wouldn't be any major positive or negative effects that I know of.

If the network had 10x more mining power, the main benefit would be security against 51% attacks, since an attacker would now need 10x more mining power of his own to mount such an attack.  (Of course, if mining hardware became more efficient in the meantime, this might not actually increase the costs of such an attack versus today - but they would still be 10x higher than without the mining power increase.)

There wouldn't be any long-term improvement in confirmation speed, since as you say the difficulty would adjust to keep the block time at 10 minutes.  (If all the mining power came online at the same time, there would be a temporary increase in confirmation speed for the first few days, since the difficulty adjustment happens only at specified intervals and the maximum adjustment at each such interval is by a factor of 4.)

I am not sure what you mean by "censorship resistant".  A mining power increase wouldn't do anything to help prevent a government from trying to block Bitcoin traffic from the Internet.  

There wouldn't be any other major end-user effects that I can think of.  Resistance against 51% attacks is the main one.