On reading lists of projects and businesses the entrepreneur CT Russell was involved in, it seems a wonder he had any time left for his religious marketing. The WTBTS frames his biography with the family drapers business being sold by him to support the Watchtower... but this is a wrong emphasis. As you say Terry he was a wealthy man and he worked very hard to make money all his life aside from the Watchtower.
I read that his safe had more than $1,000,000 in it at the time of his death which would translate to around $18,000,000 today. He was a money driven man and I feel that his religion industry was just a part of his business empire rather the consuming whole.
Nevertheless he had an inquiring mind but was limited academically and therefore subject to the hype of Biblical and esoteric writings and beliefs. I can't help thinking that the Masonic influence was present even though he publicly denied membership to them. There was something about his beliefs which fed the ideas of elitist knowledge given only to the privileged. Such being found in Paul's writing and therefore striking a correspondency in him as being God's channel, especially if he had narcissistic tendencies.
All JW leaders except perhaps Knorr were/are narcissist, are they not?
Russell had wealth and a business drive and also the religious conviction in finding the holy grail of getting the secretly coded date of the return of Christ: 1874. With Christ already ruling in 1878 as he thought, the next year he started the Watchtower and immediately made money from it.
His ideas were totally wrong and a prophetic failure but the Watchtower was able, and nearly continues to be able, to propel the followers minds towards a fictional but money making doomsday.