The gauges on the my 2014 Plus 8 occasionally mist up. Exactly the same as on the Roadster I owned previously.
Both cars were and are housed in a dry, warmer than ambient temperature brick built garage that is essentially a part of the house. So the air in the dials is usually dry and warm.
In the winter, when it is cold outside, the dials will must up, not to the point where I can't see the dial, but enough to be mildly irritating.
The flat spot issue is almost certainly due to the engine's newness. The "crate" engines are bought in by MMC, put in the car and checked to see they work through a short road test. They are not run in.
No modern car engine is run in by the maker (other than some of the exotica): the 2.0L turbo in my Mercedes AMG A 35 came with strict running in instructions for the first 1000 miles and moderate restrictions for the second. Initially it was a bit disappointing but now, at just over 2000 miles it is a changed animal.
The price of your car reflects its hand built nature, but with any bespoke product there can be issues that need sorting out. As others have said, give it 2000 miles and then make your dissatisfaction clear - if it still exists.
Morgans are an acquired taste: comparing my +8 with the A35 is pointless. Both have similar performance: the A35 is a series of networked computers that make the car perform, the +8 has 2 interlinked computers that run the engine and gearbox, plus an ABS system. Your car has but one engine management computer: MMC use a standard map, which may not be optimal for all drivers requirements. There after market alternatives, but MMC simply do not have the R&D funds to explore every option.
I agree with Hamwich, owning a Morgan requires the owners mind to be re-calibrated somewhat. I hope you make the transition and learn to enjoy your car for what it is. I feel that owning a Morgan is like being in a relationship. As with all relationships it is pointless to expect that one partner can change the other: that is a sure route to unhappiness.