Short Answer: No. Not even close, TBH. Major Chests give some much value in cards that the Merits and Energy are essentially bonuses for buying the chests.

Longer Answer: The return in cards (Reward and Gladiator) is more than the cost of the Major Chests- when compared to the cost, in Glint, of buying those cards. The Energy produced is just a bonus, giving you a bonus day or two of Battles each season, with a corresponding boost to both Glint and SPS Rewards. As you say- for anyone other than new players, the potions gained from chests are of negligible value.