I'm a little late to the party but I have a few observations:

1.  Google maps is generally not great at cycle routing, indeed many countries don't even have that option enabled.  It's fine if you are in a town/city and are routing to a hotel or tourist place but it may route you on main roads if you have to use the driving option.

2.  Mobile phone screens consume battery at a dreadful rate especially if the brightness is maximum to cope with sky reflection.

3.  Remember that on the flat tilting the phone to be "perpendicular" to your eyesight may work but if you are climbing or descending that may not work plus you will always have an element of sky peeking out from behind your head.

4.  Komoot voice navigation on a mobile with screen turned off does not consume lots of battery so that could be a good option.

5.  Mobile phones are, generally, more expensive than bike computers and less weather resistant.  Some claim IP68 standard compared to IP65 for a Wahoo but I'd trust my Wahoo more in peeing rain.

6.  Not all bar bags clear covers allow screens to work with touch so you may need to stop and check more regularly.

In my experience stem length doesn't affect steering behaviour which is controlled by head tube angle and fork trail. Handlebar choice, however, can affect how easy it is to steer the bike. For example, wide bars need for more hand movement but less force than narrow bars.

Yes! Nicely stated JohnR and in my experience spot-on and proven time and again for me as a hobbyist framebuilder. Proven also on my old fleet rental/now Enduro-Allroad bike...
https://thorncyclesforum.co.uk/index.php?topic=15149.msg114099#msg114099
...that has a choice of two Thorn Sherpa Mk2 forks, one providing 40mm of (relatively) low trail, the other 57mm of neutral trail, both replacing the original (super weighty and non-compliant MTB) fork that provided 68mm of (relatively) high trail, all with 2.0in tires. My favorite on this bike is the 40mm for general use.

Bike was originally fitted with a 110mm stem and 620mm straight handlebars, replaced with 50mm stem and 420mm shallow-drop/compact reach handlebars.

Weight distribution effects handling, so if changing the bars has an impact on that, you will notice it.

I've also found this true in my experience, Paul.

Best, Dan.

When I last bought silk tubs for my fixie they were around £100 each.  The premium-brand tyres for my Land Rover were also £100 each last time I bought them.  The main difference is that the silk tubs generally lasted somewhere between 1,000 and 2,000 miles, and I usually get 100,000 miles from my Land Rover tyres. 

If I compare tyre cost and wear rates with my more typical bikes and cars, then bike tyres still end up costing more per mile.

+1 for the coin method.
Mine loosened enough to use the pin spanner.

I read someone (Andre?) mention that they tilted the grip section of North Road bars down thirty degrees from horizontal

Yes, that's me, and on this forum, so searchable. I will shortly have to go shower and change into a pink shirt and a blazer so I can take my wife to lunch, so I'll just give you the headlines.

The ergonomic purpose of handlebars, which you break at your own longterm risk of repetitive stress injury, is simply to hold your wrists straight under most dynamic operations. That's why experienced cyclists on drop bars often hold the upper straight section of the bars, not ideal but better than the unergonomic horizontal actual grips.

North Road bars fitted incompetently with the grips horizontal, i.e. parallel to the ground, will bend your wrist unnaturally unless they're about level with the fork crown. North Road Bars fitted upside down on short top tube bikes make excellent moustache bars and is another option to match your reach on an existing bike to your desire for straight wrists.

Essentially there are only two correct ways to fit North Road Bars. The first is the way I do it, with the handgrips turned downwards. The 30 degrees isn't set in marble. It depends on the top tube length, stem length and your desired back angle, so that when your wrists are straight with you in your desired riding position, you've finished adjusting.

Two more things are very important in your choice of North Road Bars. The handgrips should be for their entire length outside your shoulder width, and the length of the handgrips should be the maximum you can find because of the number of controls you want under your thumb on a modern bike. My preferred North Road Bar width is 620mm, but I'm a large guy who sits very upright on my bike, so most cyclists will probably be happy with something in the order of 600mm.

Good luck.