I would suggest reading the CF threads on
WiFi antennas and connections so you can get an idea of the
equipment that works best on cruising
boats. And, of course, anything you are dependent upon a "provider" for maintaining and monitoring his
WiFi server, the less reliable a continuous unbroken connection will be in general.
Beyond that, the only "sure" way is to invest in the same
equipment and services the "big boys" use like those mega-yachts you see with up to half a dozen gigantic domes perched on their 5-spreader rigs. If you intend to make serious
money in a serious business like Forex or other "options" markets then you probably need to be ready to spend serious
money on your equipment to be able to compete.