How much do you reckon the Panther will cost?
If it's going to have 2000 tons of cargo (like the Elite II version) .
I crunched some back of an envelope numbers.
The T7 carries a little under half of what the T9 carries (naked, pure cargo) for about 1/4 the price. The T9 theoretically carries about 1/4 of what the Panther would carry, so all other things being equal, I estimated about 8 times the price.
But honestly expect a "top of the line end-game + It prints money" premium on the backend of that-. If the panther carries 2000 tons I'd expect it to come in at 586 million - stock, minimum (this is purely 8x the price of the T9, no other premiums added).
I hope it carries 2k, but I don't expect it to, maybe 1000 with a long jump range (anaconda), or 1500 with "T9" type jump ranges. This is all guessing. If it does hit 2k, expect it to be T9 jump ranges fully loaded. If it ends up being 1k expect it to not only have "anaconda" range, but be tanky/good hull high shield possibility.
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The other thing you need to look at is what exactly are "end game ships" - They are essentially "newgame plus" ships where money is no longer an object in the form of progression so earning potential isn't really a major factor.