Well, just my two cents on your concerns:
1. Battery range does not surprise me unfortunately. I'm not sure why Rize went down to a 15ah battery, as that's quite small for the Ultra. It is a battery hog. I have the 19ah battery on last years RX Pro, and in PAS 3 I get as low as 15 miles (25kms) in cool weather, up to 25miles (40kms) in warm weather and ideal conditions (To 20% battery, where power begins to obviously drop off). I can stretch that a little if I run very conservative and just use PAS 2 with a tiny bit of throttle on hills only, but I don't ever hope for more than 30miles. By comparison, my Rize X (750w hub) does at least 50% percent better, and 70kms is easy at PAS 3 and one battery. I carry a second battery on the RX Pro for day rides so I can get at least 70kms without any range anxiety.
2. It is geared lower than most need. In stock dress I also never used anything below 3 and spent a lot of time in 8 & 9. I wanted to be able to contribute more pedaling at higher speed, so I swapped in a 49T front chainring and that shifted my gears about 2 cogs. I now seldom use 9 below 50km/h, but I use 2 and 3 regularly to get going, really steep hills, and for tight single track trails. That range works better for my use, and I still don't need 1.
3. My Ultra motor also makes that slight intermittent rubbing sound, but I couldn't find any obvious problem and it's at nearly 2000kms with no change/deterioration. I plan to tear it down and re-grease it this winter, so we'll see if I can find anything obvious then. The Ultras are generally know to be noisy due to metal gears - supposedly re-greasing with certain grease (Mobil SHC 100) helps - we'll see... Certainly post up if you find the clear cause.
A couple of things I had with mine in the first couple of months of use last summer included; The right crank arm worked loose twice and was identified by an intermittent clicking - finally tightened the bolt a little over spec and it's held fine since. I found a few trim bolts like fender bracket nuts also worked loose within the first couple hundred kms - all were fine after a good retightening. My taillight wires came out once - was fiddly to fix, but has held since the repair. I did have a short lifespan on my first rear cassette, but I commute hard and fast with a heavy rider and plenty of cargo. I posted a thread on my subsequent modifications, and they have held up fine for 1,500kms with measurable life still left in them so the tweaks worked well. I've made a number of comfort upgrades, but the basic bike is quite reliable and meets my needs well.
So I'd go over all the bolts at the start, and again after the first couple hundred kms before any can escape on you. And experiment with tire air pressure. More pressure improves the rolling resistance up to a point, but there should be no need to max it out.