If you plan on having more than one...Ninja, is easier..
You have to do 1 round trip per character...for the Samurai....and if the 'Salads' are still around...that can be fun.
But IMHO....the Samurai's 'Tiger strike' is very useful, early on...and you can always do Ninja later.
There are plenty of points...in the dungeons, of the shire
You can easily do, both...before 'Dragon Spire'....