Which is a better long-term strategy - keep building one site/brand or build multiple sites/brands?

Hey, I'm looking to really start expanding my business this year. I seem to make sales pretty regularly, but I have never once felt that my income has gotten to the point where it feels stable and secure. That is because I have only been selling one single thing, which is a lifetime membership to a website that I have continuously been adding content to for almost 5 years now. The site is pretty massive!!

Selling lifetime memberships is appealing to the market, but it requires a consistent flow of new customers in order to remain profitable. The obvious solution is to change the model to a recurring model, which I have done before. I have never tested a recurring model for longer than 2 weeks though because it always results in an instant drop in income. During the 2 week testing period(s), I have always still made sales nonetheless. The fact that this is now my full-time job and primary source of income, those income drops can be scary. However, I feel that if I could just suck it up for at least a year, I would find myself in a much better position than I am in today. Over the course of a year, I will acquire many monthly and annual subscribers and I will make a bunch of one-off sales as well. Fighting through that initial income drop is the real challenge though...

An alternative that was suggested to me here on this forum was to expand by creating more websites. I am actually in the middle of a new 6-month project where I am creating a new course. I was planning on following the advice to build an additional website, and to host this new course on an entirely separate domain. At that point, I would then have 2 "products" instead of just 1. Essentially, it would be an entirely new "brand", and I would market it using mostly Facebook ads. I'd let my current buyers list know about this new site and offer them a discount.

While this 2nd site thing does sound like a good, safe idea that won't affect my one and only income stream...I'm still wondering if it is the best long-term strategy though? I already have a "brand" that I have been building for almost 5 years now. I have a loyal following with a private Facebook group. I have hundreds of great written reviews, and I'm starting to collect video reviews as well. The seed has been planted, and it's continuing to grow. As I said, my site is already broken down into individual courses, but I'm still just selling them all as a "package deal" via a lifetime membership. "Changing the model" to a recurring model with one-off options can be done at the snap of my fingers. "Changing it back" could also be done just as easily. Therefore, it's very easy to run tests.

I was thinking that I could give the recurring model, with the option to buy one-off purchases another shot. I could then host this new course that I'm making on my current site and market it using Facebook ads. This would re-introduce the risk of taking an income hit for a while. However, ultimately it may be the better long term strategy.

I'm wondering what your thoughts are on which you think is the best long-term strategy?

Thanks!


TL;DR -

Option #1 - Host this new course that I am making on an entirely new website. This would result in having 2 separate websites. Keep site 1 at a one-time price since that has proven to result in steady sales. Market this new course (which is hosted on site 2) as an entirely different brand, but offer a discount to my current lifetime members. This option is the risk-averse option

Option #2 - Just stop selling lifetime memberships and switch the model to a recurring model, also giving people the option to buy single courses for a one-time fee if they didn't like subscriptions. I'd then host this new course on my current site and market it using FB ads. The leads that I pick up from FB ads would then have several options of things that they could buy from my site, including the "full access" option which would be the recurring fee. This option is the riskier option as it will result in an initial income drop, but my gut instinct keeps telling me that this is what I should do.