My wife and I are big fans of Canada but always go to The Rockies for winter sports. We'll be there again in a couple of weeks.
However, I fancy a summer time trip with the bikes and my wife always mentions Nova Scotia (I do a lot of tours in Old Scotia so probably ought to see what the newer one is like!) We have a friend who works in the University in St Johns and there are direct flights from UK to St Johns in the summer so that ought to be a good starting point. I would intend using bike boxes for the transatlantic flight then leaving them at a hotel or with our friend if she has room.
I have a few questions for anyone with experience:
1. other than pedalling would there be any other means of moving bikes around such as buses or trains? Say if we did an A to B tour rather than a loop.
2. I haven't launched into Google yet but are there any reliable resources for cycle routes available?
3. where should we go? My wife would prefer to avoid big hills, undulations are OK, 40ish miles a day is probably enough (60ish km). She has declared her camping days to be over so some sort of lodging or hotel would be preferred each night. Costs aren't really a problem but most certainly don't need 5 star hotels and fine dining!
4. midges/mosquitoes/annoying little flies, what's the deal? I've heard rumours!
5. I'm suggesting a summer trip but when is a good time for decent weather (we live in North Yorkshire and it has been cold, wet and grey for several months now, we would like some warmth on our backs if possible) We have appropriate gear for Scottish weather but would prefer to avoid using it if we could.
6. Should we start somewhere else? St Johns is convenient but anywhere with a direct UK flight would do. I'm suggesting east coast as we've never been but am open to suggestions.
7. We will be on our Thorn bikes so reasonable roads would be preferred but we are happy with decent gravel forest roads or old railway tracks.
8. and if we can throw in some whale spotting that would make my day.
We're retired so don't have any time constrains but would be thinking of a 2-4 week trip
Any help would be much appreciated
Nick

Stay with tubes. 

For touring, I drop my gear range down to 36 chainring and 16T sprocket.  That is very similar to your 43 and 19 ratio.  If it is too steep for that gearing, it also is too steep for me to pedal while keeping my heart rate in a reasonable range.  Thus, I get off the bike and walk it up the steeper hills.

Have you ridden much on rough trails before? 

I'm heading over to Canada (from Scotland) this summer, to ride south for around 1000miles to Jackson, Wyoming on the Great Divide route with my son.

The GDMBR tends to get talked about today as more daunting terrain than it is. Once the bikepacking scene took off, it embraced this route which meets the Bikepacking.com definition because it is majority unpaved. However, before that, the GDMBR was commonly regarded as a touring route and people rode it on conventional touring bikes like the Surly LHT, with 2.00" or 2.15" tires. Loads of blogs were written about this, some of them are still up today. So, if you can fit 54 mm, you’re already well prepared, even if you might want to take advantage of being able to fit something slightly wider in front.

On the same page he also explains why you're likely to get 20,000km + from an uncovered KMC X1 chain with minimal maintenance.

I think that depends on where and when you ride. I live near the coast and ride in all weathers, so when it rains the tyres pick up wet sand and mud and a rim brake sprays it over the chain, even when I don't go off-road and keep to tarmac.

The best I have managed so far is 8,300 kms with an old type bushed 1/8" chain used on a hub gear bike. This was long before I knew about the ChainGlider. More typically, I would get between 2,000 and 4,000 kms on a derailleur bike. Bromptons are worse, typically 2,000 kms or less, probably because the transmission is closer to the ground and picks up more muck.

KMC advertises 3,500 kms plus for the successor to the X1 and 10,000 kms plus for their long-life 1/8" chain if used with their own 1/8" chainring and sprocket.

The photo attached shows the results of one of my first rides with a ChainGlider The wet sand on the outside of the ChainGlider would have gone on the chain if it wasn't covered.

In my experience, a ChainGlider keeps most of the mud and sand off the transmission. Water gets inside when it rains, but it drains out. A ChainGlider works for me to significantly reduce transmission maintenance.

For all the recommendations that the Chainglider gets here from a member or two, Thorn/SJS did try to dissuade me from buying one from their own shop a few years ago, calling it a “poor piece of gear” that had disappointed them in their own testing of it.

It’s also worth pointing out that some of the most popular long-haul bicycle-travel routes today involve water crossings. A chain is going to get dunked several times in just one single day on the Baja Divide, for example. A Chainglider is downright counterproductive then, it would trap water inside.

I have now put over 20,000 km on my belt drive and I am very satisfied. I think it is worth it in time savings alone, as it does not have to be cleaned or lubricated. No more expensive trousers being stained with oil, too. I have never even had the noise that some report, except for when I rode one wadi in Oman where the dust must have been of a peculiar composition, and then merely pouring some water over the belt was enough to make it quiet again.