Proper Simulator Scaling

Hello, in making a simulator, I would like to ‘simulate’ the proper growth curve to keep players pushing for that next milestone, without feeling too much like a grind. I would appreciate your thoughts as I have very little experience in this nature, but I believe that most simulators do not get it right. (as explained below)

My plan:
My simulator does not have levels of experience, but I will speak about levels as in your starter sword is level 1 and when you have gained enough resources to get the next sword then you will have a level 2 sword. I would like a player to spend about 3 minutes into the game, learning the controls, and doing what they are supposed to be doing to gain the next level in their chosen attribute. I can control this slightly in the beginning with a tutorial and quests like many games do. My thought is to then double the gains they are receiving while tripling the amount of experience needed to gain to get to the next level so it will take about twice as long as the previous level. So if it was 100 experience to level 2 and it took 3 mins to get it, you would need 300 to get level 3 and it should take approx 6 mins of playing the game properly. level 4 would be 900 and take 12 mins.

I know I can speed up the progression or slow down the progression by changing the base requirement, changing the rate of gain, and the scale of the requirement, but this is what I personally don’t like about simulators. It is like they run out of content so they change billion to trillion and QT and QX and SC or whatever it is and get so grindy. Maybe this is the only way they can be profitable?

I would have to consider other modifiers as well such as rebirths, gamepasses, and player skill but I wanted to try to get a starting point and get advice on if an exponential curve was required with simulator progression or if a linear model could be successful.

Thanks