No, just no. Those are awful prices. This isn't going to encourage anything, it's just completely displaced Premium Scrap in comparison to other ores.
tl;dr you're doing a commodity that's the same price as Niobium Ore but for twice the journey.
You're forgetting a few things, such as:
Premium scrap mines faster. Mining transports for P-scrap factions are superior to mining transports for ore factions both in combat and capacity. People hauling scrap are also less likely to be pirated than people hauling ore. A corporate transport full of ore was always the "juicy" victim for pirates. The insanely high P-scrap price we had for a while was starting to offset that image. P-scrap routes have some wonderful back-trades as well. Additionally, it is scrap, after all, it wouldn't make much sense for it to be so much more valuable than diamonds, gold, etc. Scrap simply isn't supposed to be as profitable. And this is coming from a junker congressman. I think the new P-scrap prices are fine. I was making way too much money before.
However, to make these routes still worth doing, contraband on the backroutes (and contraband in general) will need a little boost; smugglers need the boost anyway for the extra risk they take. After all, scrap is supposed to be the junkers' cover business, while we make our real money through less legal means.