If youre looking to get better at mastering these two concepts, the best advice I can offer is to play some games of Commander
It might be a better choice for Living End to return to the black creatures instead, so it can make use of Grief
Its hard to block profitably, but at the same time, its risky not to block it
The two cards Live Fast and Die Young are tied by their art and flavor, which shows how fleeting life can be
I think were going to see a big glut of copies hit the market and this wont be a pricey card
If you want to play a longer more mid-to-lategame style deck in Mono Red that interacts more with the table, well, it gets more challenging because it makes Mono Red's inherent weaknesses more glaring: subpar card draw and ramp, subpar answers to creatures, minimal options for enchantment removal, commander protection, and recursion, things that get more pronounced as the game progresses