With the addition of Unholy Heat to Modern, not even Lightning Bolt has been able to fully withstand the power creep of the last few years, and I personally would place it below Unholy Heat in power level when taking into consideration the context of the Modern metagame
Looking back, drawing three cards for 4 mana at instant speed would be kind of broken
Assuming youre going out of your way to cast a lot of those spells, or even if youre just running a few bits of interaction and some card draw spells, youll have a lot of flying Creatures very quickly
Throughout, Wizards of the Coast has consistently added new mechanics and abilities in each subsequent set, some of which have had a bigger impact on evolving deck-building strategies and the overall meta
You can take care of aggro threats with board wipes like Crippling Fear, or counter early- and late-game spells with cards like Counterspell
Cecil, Dark Knight is the latest in aggressive black creatures and is so aggressively pushed, we might have a long term staple