Remember that copied spells already have their costs paid, so spells with additional costs are great for copying along with X spells which retain the same value of X
If Three Tree Scribe leaves the battlefield without dying at the same time one or more other creatures you control leave the battlefield without dying, its ability will still trigger once for each of those creatures, including itself
Jecht, Reluctant Guardian A 4/3 for four with menace is pretty average, but thankfully, the backside of Jecht is the side that really pops
The main takeaway is this: SPE cards are really valuable, MAR reprints are mostly good, while Marvels Spider-Man (SPM) is just okay in value, outside of a few rares and mythics
Side-loading pockets and low-friction material help keep cards in place