You should attempt to have the minimum amount of seams while still avoiding stretching so yes ,stitch what you can still keeping your UV's flat.
If you have to have seams then try to hide those in parts of the model that won't be seen often or at all if a still image.
As a side note you should scale the UV's up to fit into the 0-1 space as tight as possible so as to give your texture the maximum amount of resolution you can on the texture map.

Looking at you object perhaps headus UV was not the best choice to map it since it is a pelt type unwrapper and a cylindrical map projection would suit your object better.If you don't already know this ,you can select faces on your object and map only those faces elected and build up your UV's that way..for example map the outside faces of the cylindical part of the object then the inside separately then perhaps the squarish part separately with a planar map. Finally sew what you can together.