No kayak will perform well in all these environments. Boat technology is rapidly changing, kayaks are constantly being re-designed and updated. While there is something to be said for a wide stable kayak, there is merit for purchasing a boat that you can grow into as your skills develop. However, if you want a kayak for occasional weekend use, a wide stable boat is appropriate and will give much pleasure. If you are planning on doing long distance trips and overnight camping then a longer larger capacity kayak that can handle choppy water is the right choice.
Paddle selection comes next after boat choice has been made.
There are as many paddle designs as there are kayaks. They can have oval shaped shafts, which cause less finger fatigue, cupped blades for special stokes, and asymmetrical blade shape for minimizing rotational torque. An approximate guide for paddle length is based on your height and boat width. Sometimes a 240 cm or 8 paddle length works well for coastal touring where a steady cadence is maintained and the paddle blade is kept below the top of the paddlers head. Aggressive paddlers tend to go with a shorter paddle and a high stroke or entry into the water close to the side of the kayak.