I'm a software developer working remotely for a company in a very developed country. I started working for them for a very minimal amount of money, because I just wanted to get started and hoped that once they see what I'm capable of, they will offer me better conditions. When I say minimal amount of money, I mean 20% of what would be an acceptable amount for someone doing what I do, based on my research. Although I've gotten a raise after 6 months, the payment continues to be very low compared to the overall standard. Recently, they hired another software engineer who I've had to teach for the first two months about how we do things at the company. I checked her UpWork profile (she told me that the company found her on UpWork), and I found out that she was paid at least 3 times more than I am. I thought she was a good developer and she deserved it, but 6 months have passed and she still counts on me about many things, while I am kind of the leader of the team now, after one colleague left.
I don't want to leave this company because the organisation that the development team has is amazing, and the people are great and I learn a lot from them. Still, I feel like the company it taking advantage of me. I know I should ask for a raise, but the problem is that at this point, I think it would take something like a 70% raise to my current salary, to be close to job market standards. I don't want to come out as arrogant for asking for such a big raise, but on the other hand, I feel like I'm being taken advantage of, and it's becoming very stressful. Furthermore, I'm paid on a daily basis, meaning that if I want a day off, I don't get any money, and that is also very inconvenient, so I've been thinking of asking for something like 2 weeks paid days off a year.
Has anyone ever been in a similar situation, where people doing much less than you are being paid 2-3 times more than you and given better conditions in general? What would be a good way to solve this without breaking the relationship with the company, because I really like the development team, so I want to stay here.