Hi Photo... Your choice of boats for adventure is impacted not what is said on this forum but what you can glean as common knowledge and what you want to accomplish.
I had a 15ft trailer boat, that the manufacture helped a 20 something sail from LA to Hawaii. 30 days.
I met a woman in our marina, who (with her husband) sailed a 24 foot boat from LA to the Marquees Islands in the South Pacific then on to New Zealand.
Any one can sail almost any boat any where, if the weather is favorable, and there are enough supplies to stay alive (and surprisingly we can stay alive for a long time on very little if we are determined).
Granted there are differing opinions as to what is an enjoyable passage and surviving a passage.
Here is a link to info on Island Packet boats and others that sailors consider "Blue Water Boats".
http://bluewaterboats.org/island-packet-31/
You may want to define "Comfort", at least to your self, before you specify a boat and it's size for a Sail across the Pond.