I agree with you. It should be an oppurtunity to exchange this soulbound-cards against other soulbound-stuff without unlocking them for a fee, at least for the cards above max-level.
If this are point for other cards or already exsiting soulbound stuff like merrits, bloodstones, powerstones, dec-b, power-sources or potions (don't sure if I not forget something) can be discussed.
We have so many soulbound-stuff that it should really be no need to pay a fee for this cost.
As far as I know this cards has no print-limit, so after print-out splinterlands could even make a pack from this cards and sell them for newcomer to a price like the Rebellion-set.