A lot variables to necessarily give you one right answer, and it all basically comes down to your commitment to getting better and the time you have to practice and play.
If time is not a factor and you can get out a lot, there is no reason you should not be throwing a wide array of discs in stability and speed. This will teach you what your body is and is not currently capable of as well as seeing a variety of types of flight. Almost all discs have the potential to travel just as far as any other disc no matter if we are talking putters or high speed distance drivers. It all comes down to circumstances of the conditions and courses. You are only going to find this out by throwing everything.
You can read about it all the time, but until you experience it, how would you know that a putter on a downhill shot will garner you the most net distance? How would you know that a super high speed driver will flare harder and higher in the air off an intended ground bounce than a putter or mid? There are just so many different ways to get a disc to the basket that it seems assinine to limit your practice to only one kind of shot because you only have one kind of disc available if you have all the time in the world to practice.
Yes, people are mocked all the time for throwing a Boss on a 200 foot hole, but at the end of the day if it works for you and your score is lowered because of it, where in the rules does it say you HAVE to throw a putter or mid in that distance range? Getting a birdie with a Boss is just the same on the scorecard as getting a birdie with an Ion. Now, if you are the kind of person who is throwing a Boss and is lowering your score from a 7 to a 5, then we will talk about disc selection.
However, if time is an issue, then it is better to lock in one disc and throw that almost exclusively. By being forced to throw a singular disc on varying lines and circumstances, you will truly know what it is capable of. This will create a higher level of trust of what lines you can accomplish, what release points work best for those shots, power to snap ratio you will need, and what wrist angle you will need to use. If time is limited, it is better to throw 1 disc a million times than a million discs one time.
Sorry about the mixed signals, but again it all comes down to the amount of time you can dedicate to practicing.