It's hard to say if you're on the right track, without having that much detailed information about your goals. As a first thought, I guess one thing to be wary of is that if you're starting out using private label products, it can be hard to justify to the consumer what your point of difference is. You've stated that you want your skincare products to be plant-based, and the makeup to be a mineral line, but as a consumer that doesn't really tell me how your line is going to be different from anyone else's... will it be based around organic / natural ingredients? I'm not attacking your thinking here, just challenging! Developing a firmer idead of what your brand is about and what it stands for though, will possibly help to narrow down your strategy - where do you want to be selling, what price will it be (and what can you justifiably charge), who will you be selling to? Etc.
Also, I'm curious to know how you intend to distribute your products - will you be a solely online business, distributed through salons, larger retailers...? Knowing who your buyer is will make a big difference in your approach, both in terms of what you are offering, the margins to the seller, and ultimately your bottom line.
These are just a few random thoughts to get you started.. for me personally I would mainly be thinking about the strategy to build your line to a level of "critical mass" at which it becomes possible to invest in developing your own products, and then focusing on how you get there. I would start gathering cost estimates from potential suppliers and working out an initial P&L, as well as your sales goals. I think the hardest part about launching a new product or new brand is just in the initial gathering of information, as there is a lot to consider. But I wish you luck, it's certainly not impossible!
