Hold on to your hats because and get comfortable because this is going to be a long ride, ladies and gentlement.
Mara's Balm has been dominating the battlefield since its release. It has been doing so because currently there is no other set or skill that comes even close to doing as many things at once. MB has many effects tied to it and they all require the player to do absolutely nothing to reap the benefits of the set. Taking direct damage while you have negative effects on you (just like every single other person in pvp)? Free heal and purge. Hiding behind a tree while you have DoTs on you? No problem, free heal and purge.
There are other purge sets out there, but none of them compare to MB. Why? Because what makes MB stand out is the healing it provides. No other purge set heals the player when negative effects are removed. They may remove all negative effects, but with cooldowns way longer than MB. They may remove some negative effects, but no more than three at a time. MB removes everything...every...15...seconds...
I hold true to my claim that sets should never outperform skills. MB is doing exactly that by effectively putting purge/cleanse skills out of commision. The most powerful cleanse is the Purify synergy (meaning players can't spam it) and it costs almost 5k magicka to cast.
Cleanse is the closest to MB in terms of performance, but it costs and outstanding 8k magicka per cast. Even if a player had 30k health, Cleanse would only heal them for 4.5k HP at most. MB heals for 10,050 HP.
Even the "cheaper" version casts an arm and a leg to cast
There are even less attractive purge skills that have a much lower purge capacity. The strongest Necro purge only cleanses 4 negative effects. While it is the most efficient skill in term of cost to purge ratio, it offers no healing, unlike MB.
Compare
"So what?", you may be thinking. Mara's Balms is the equivalent to Caluurion's. During the Caluurion's meta (which lasted years), people could not possibly survive a stealth attack from Nightblades. Now, MB is making it impossible for people to die. This set needs to be fixed and it needs to happen now. The PvP community will not allow another set of years to go by to fix it like we did with Caluurion's. Get rid of the burst heal, instate a purge cap to 5 (which would be en par with the strongest "spammable" purge: Cleanse). It is unacceptable that a single set can have all those effects jammed into it.