A lot of good info already. I moved to Ct. in 1984 after living in Jersey, NYC, Jersey again, then Buffalo NY, and off to Ct. Ct. is small but more rural than you would think. If you leave the coast, I95 and I84 you are in rural areas almost immediately. Yet NYC and Boston are easily accessible.
It is the most blue state in the Republic. Both Senators, all House Reps, the state legislature in both the house and senate, the Governor, the AG, the Secretary of State, etc. It has been mismanaged financially and has a lot of debt issues including reserves for state employee pensions, etc.
So it is expensive when you add up all of the taxes and other ways the state can get money from you.
I am in northern Fairfield County and housing is still "reasonable" compared to the southern part of the county but compared to NY and NJ the one thing that is cheaper are local taxes.
The rural roads are narrow, hilly and winding.
For those who fish and hunt it is actually kind of a sportsmen's paradise. There are a ton of glacial lakes, impoundments, reservoirs, other natural lakes, large rivers like the Housatonic, Connecticut, Thames, etc. You have saltwater fishing in LI Sound which is extremely good for many species and then all of this freshwater for trout, salmon, bass, pike, walleye, anadromous species like shad, stripers, herring, etc.
Deer hunting can be exceptional and there are lots of public lands. Bow season is Sept. 15 - January 30 with six tags, as an example. It is not a one buck state like Pa., with all tags state and private you could take a half dozen bucks but no one does and some areas have years where there is almost no limit on does if you bother to check them in and access replacement tags.
There are also bear and moose but no seasons.
We go to Florida for the winter so we escape the winter but being close to the sea the weather is rather moderate especially along the coast. Colchester is going to have a more moderate winter than the northwestern Ct. hill country.
I would jump all over the deal in Colchester. I don't know your lifestyle but an old New England farm house style main building along with a barn and 20 acres is really big money in Fairfield County and if you can move laterally into this setup due to advantageous pricing I would grab it. Take a long weekend road trip and see the area and good luck with whatever you decide.