stardust cost for pkmn with lower base stats

I would like this ...thumbs up!!! No need to discuss;)

You're right. I wait to power up my other mons. But i'm a collector so I would glady do that. But on this moment it is just to expensive.

There would come an interesting point: You could safe a lot of stardust powering up Dratini and evolve it, when it has desired size.
Problem: You then still get a random moveset.

Now it is easy: First evolve, then power up. After this hypothetical update it is more difficult:
First evolve to be sure about moveset or
First power up to save stardust.

Interesting idea.

Eventually, people will not put stardust to low base stat pkms. They will rush to level 30, catch max level pkms then evolve. The evolved pkms will be high enough to secure a place in gyms. Stardust is still saved for those Dragonites/Snorlaxes/Rhydons ... to come. At the end, everyone just need around 10 highest pkms to collect coins. To blow hostile gyms away, we don't need those level 31-40 pkms, right?

My experience is: gym gets attacked, gym goes down. Defenders high in gym do not matter, as often only engaged after gym lost a few levels and is already lost. More efficient to put quality defender low in gym to ward of attackers while there are still high prestige levels left.

Just change gym rankings to use mon level...

All problems solved with mon diversity...and now strategic gym placement for better defenders (Poliwrath, Slowbro, etc...)

It's an interessant purpose, although I think it won't change the pokemon we see at gyms. When talking about defensive pokemon, it's all about the CP the pokemon gets. I'd still spend more stardusts to get a 2600CP Vaporeon instead of spending less to get a 2300CP Slowbro. Although, I think that your purpose would diversify the pokemon we use on offensive, as they are much more flexible (the CP is not all that matters, as it is on defending gyms. On offensive, the typing also work together and make that 2300CP Slowbro more valuable).