There are a couple of electronic solutions I would consider. There are several internet based house monitoring systems available these days. Some are sold/leased by local cable companies, but others are generic. They can monitor everything from security access to motion detection, heat and air conditioning, humidity, etc. You can even adjust each of them from your phone. Not sure where you live, but in most parts of the country, a failed HVAC system can be a nightmare. In cold climes, pipes break (maybe you even want to drain these). In humid climes, a mold farm will grow in places you'll never reach, within a couple of weeks of losing dehumidification.
There are also internet based video monitoring systems, where you can buy the hardware once and see what's going on from your phone, tablet or laptop.
Each of these would require that you maintained wifi internet connectivity at the house. You may still require someone that could go there, from time to time, to reset a wifi router, etc. Of course, if you identify a problem, you'll also need a plan to respond.
How about a house cleaner? Essentially just keeping dust down, which would be valuable and probably not expensive (unlike cleaning after a home in use). If you trust them (that's big), they would also serve as a check on the place. On the other hand, they could serve as the broadcast of you not being around.
I have family that did the snow bird thing for years, summers in the Northeast, winters in FL. They monitored the other end, via the internet, this way. They typically paid a neighbor to check in on the place about once per week, who sent them an email to confirm status. They took that neighbor out to a nice dinner as well, when they returned.
Another thought, which is very popular these days, but admittedly I would not do, is AirB&B or HomeAway. Rent your house by the day over an internet website. I know some folks actually making a fortune this way. Far more revenue than mortgage payments and utilities. You'll still need that house cleaner, which the tenants usually pay for. I think some local governments are starting to address regulation around these, from permitting to collecting occupancy taxes. You'll also need very consistent (daily, but maybe not 24/7) email access.
Good luck. I think you are very wise to consider the day you'll move back ashore, even if intermittently. Most do.