The Dire Wolf can still hang with the Stone Rhino - just having ECM available is an advantage to that chassis. But then, on the other hand I do love
Stumbles. I also find that there is definitely a
Place for Heavies running DPS; it doesn't all have to be just poke builds and sniper rigs.
I have to disagree somewhat about the variability of Clan builds versus the Inner Sphere. It's true that there are a lot more chassis - but this is generally because the Inner Sphere has no Omnimechs. The number of weapons is greater for the Inner Sphere. The Clan tech base has 19 Ballistic, 15 Energy, and 15 Missile options - the Inner Sphere fields 20 Ballistic, 20 Energy, and 18 Missile weapons available - some might point out that practically no one uses Rocket Launchers, but they're still an option, so we're counting them.
The Clan ability to swap hardpoints around to optimize weapon loadouts and placement is often underestimated, however. The reason that Inner Sphere 'mechs have so many quirks is that those quirks were necessary to boost all but a handful of Battlemechs to relevance. Even today, if you took the Clan tech base and put it up against the Inner Sphere without quirks on either side... Clantech would slaughter the opposition. The difference is more than just the extremely space- and/or tonnage-efficient weapons; it's also the ability to swap out omnipods to dramatically increase your options with a single "variant" of the same Clan 'mech.
Even at the Medium level, too - no Inner Sphere 'mech can match the
Black Lanner's combination of speed and firepower. There are a couple of IS 'mechs that could match the engine speed, but none I can think of mount MASC, and none of them have the options for the kind of light-weight weaponry that runs the above build. This isn't an "ZOMG Narf Teh KLANSE!" argument - I just think that the emergent flexibility of having so many light-weight and space-efficient options does a lot to offset the Inner Sphere advantage in weaponry.