New suspension fork - how much should I care for locking on the handlebar?

Any fork lockout per-se is a sign of suspension design limitations, one would argue. An ideal suspension system would tune the closed/open states by its own, and there are attempts to achieve that (Specialized Brain, Magura Elect etc.).

Rider's mental energy spent on making lock/unlock decisions translates to lost joy of the ride. Unless every second counts, i.e. one is racing against the clock, and needs all the efficiency all the time.

An always open suspension fork will not turn a ride over a smooth surface into suffering. A little loss, not unlikely unmeasurable, of pedaling efficiency will happen, and that is it.

Similarly, a proper fork, even when locked, will have a blow out valve to open up by itself when a rider encounters a bumpy segment. However, this situation is more dangerous than leaving the fork open all the time. It is better to foresee the need to open the suspension than to rely it to happen on its own.

The difference between lockout control placements manifests itself in how much time the cyclist needs to spend to switch it. When commuting, touring or leisure riding, lost seconds to slow down, find a knob on the fork and turn it are really not that critical. When racing, slowness is of course unacceptable and a lockout placed on the handlebar is preferable. Not that it does not have its negatives: 1. One more knob on the handlebars to mess with; 2. One more cable and housing to periodically replace; 3. Additional weight of additional components.

My personal perspective on this is as follows. I have two bikes, (n+1 rule I guess) one with a remote lock out and one on the fork. I do very little riding on paved roads. Originally I used the non remote lockout option only on the steepest climbs. While first riding the bike with the remote lock out I found myself using it much more often, long smooth straight sections locked it out, moderate climbs,locked it out,etc. As I got more miles on the bike I found myself using it less and less. Now I am back to using it only on the steepest climbs. If all things were identical, same quality of components but 20% more for just the lockout I would pass on the remote. Things however aren't always that simple. The bike with the remote lockout likely has better quality components. In theory the better components should last longer and perform better. So the real issue is are you willing to pay more for better components.

A good quality fork from the likes of RockShox or Fox will have the lockout (which is always on the right, damper side of the fork) designed to be upgradeable to remote. The lockout switch on the fork is on top of the right fork leg--very easy to reach. It takes minimal pressure to turn the lever about 180° right to lock out or back left to open. It's fairly unnecessary for the casual rider to 1)require the lockout feature at all and certainly not often or urgently enough that a remote would be beneficial 2)benefit from the energy savings derived from locking out the suspension. Especially one well tuned to the rider style and environment being riden in.

Skip the remote for now. Invest the money saved into getting a higher quality of fork, and, if you must, take 2 seconds to reach down with your right hand and flip the suspension on or off.