Scuba-Stu: "... I find myself looking to retiring from my
current vocation and taking on diving as my main source of income. My
question comes down to which organization is a better route to take? ..."
Scuba-Stu, I’d suggest going the PADI instructor route. A SSI instructor certification is dependent on the dive shop from which they earned that cert. If you leave that shop, your instructor cert is inactivated, and unless you associate with another SSI shop, your instructor cert is worthless. As a PADI instructor your certification stays active whether or not you’re associated with a particular dive shop, you control where & when you want to work. THEN, After getting your PADI instructor cert, associate yourself with a SSI shop and do a cross-over. Then you have both certs and control your scuba career future! ...just my 2 cents worth! (...by the way, I have instructor certs in both agencies)