I value lifegain really highly these days
There are definitely times when it'll be your all-star card, but I can also imagine cutting it from the deck that's not got many instants
Personally, Im so low on Lightning Strike that I wonder if Heartflame Slash could have just been cost at 1R, but even at 2R this is a card that Mono-White Aggro decks will just play and often splash some red sources for, as well as a respectable option for fully Boros decks
25-21) Doubling Season ($25), Woodfall Primus ($10), Mana Reflection ($10), Genesis ($15), Regal Force ($8) Im lumping these cards together because they often end up in the same kinds of Commander decks: big, green, angry brews that overwhelm opponents with mana ramp, tokens, fat, and utility