: I have built Tom Yost's Sea Tour 15 R. I am now looking to build a
: kayak for another member of my family. The kayak will be used
: for day trips on inland lakes and small rivers only by a paddler
: with no previous kayaking experience. Paddler weight is 195#,
: Paddler height 5'3". I am looking for high primary
: stability. I have been looking at Tom Yost's Sea Tour 15 Exp.
: and have a few questions.

: Does this kayak have good primary stablity?
: I see this kayak has a capacity of 300#. Is the volume of this
: kayak a little to high for the paddler parameters I have given?

No. Not at all. The capacity of the boat MUST be higher than the weight of the paddler and gear, or it would be underwater. When the capacity is much greater than the size of the paddler it is an indication that the boat may have good stability, but not a guarantee of it.

Most 17 foot open canoes have a capacity of about 900 pounds. Generally these carry two paddlers weighing in total between 200 and 500 pounds. They have capacity to spare even with two big guys, and much more with a couple of 12-year-old Boy Scouts.

: If it is, could I reduce the width of this kayak slightly and
: maintain good primary stability?

No. Reducing the width tends to decrease stability. Narrower boats can be faster but generally they have more experienced paddlers.

: Are there other designs I should take a look at?

Hundreds. All of them have their good points so choosing one is confusing. Think of it like buying clothes. At the high end you can get a custom tailored shirt There are lots of tailors around the world and lots of options on fabric, cuffs collars, buttons, etc. You could go nuts trying to pick just one and call it 'the best'. At the other end of the spectrum is a plain white knit T shirt. One size fits most. Either choice covers your back. While there are a lot of generic boat sizes around, builders have the opportunity to tweek these and tailor them to be a closer fit to someone. The question then is 'how good is the tailor?'
And after that consider that a change in diet can change the size of the paddler. It is bad to outgrow your shirts but it is terrible to outgrow your boat!
Don't get too obsessed with making a boat for a beginner too personalized. Make them a useful boat they can grow with.

PGJ