Urbanmech Build using an Anansi
Here you go, this is easily how they could implement the Urbanmech utilizing a STD 100 engine and make everything work perfectly kosher, so to speak, with what we already have built into MWO. Yeah, the build isn't EXACTLY canon, but . . .
-The base Urbanmech also had 11 heat sinks, so we can dump one right from the start, earning us 1 extra ton towards the STD 100 engine. The build was absurdly heat efficient, anyway, as it could only build a maximum of 7 heat yet had 11 heat sinks. I'd say the extra heat sink could have been crit-padding, but it was put into the head, instead of with the ammo or autocannon.
-It also didn't utilize maximum armor, anyway, having 96/105 (or 192/210 in MWO's doubled armor number terms) . . . so, it shouldn't be breaking anyone's hearts if we shave off a little extra armor in order to make the build fit. MWO has already doubled the armor numbers over canon values, so other finagling and/or tweaking to a mech's overall armor value is a bit of a moot point if you're just trying to make a mech build work.
-The other viable variants all have little effort needed to put them into the game using this design philosophy. The only two variants that don't have the 11th heat sink are the R69 and the AIV. Neither of those will be added, at this time, because they're not viable. The R69 has an IS UAC/10 and the AIV has an Arrow IV artillery system . . . both weapons that we're not seeing anytime soon; and when/if we do see them we'll just be able to make the variants on our own by cramming them into the Urbanmech variants we already do have (Except the AIV because that would require a missile hardpoint . . . perfectly doable if they give us the R68 with MRM's later on, however, when/if those weapons are introduced).
-This all prevents PGI from having to somehow figure out how to encode in a STD 60 engine just for the Urbanmech, thereby allowing us to have the Inner Sphere's most dangerous Trash Can with even less extra work required . . . thereby getting it into our hands faster. This is just a good move in general . . . getting the Urbanmech into our hands as fast as possible.
-This somewhat applies to the Urbanmech IIC, as well, because it uses a STD 90 engine, but with the absolutely miniscule differences between that and the 100, you can just solve the problem by either shaving off the tiniest bit of armor or giving it Clan Ferro Fibrous armor off the bat. Both solve the problem effortlessly.
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For those talking about potential variants and hardpoints, again, I had also made mention and did a pretty hefty bit of writing on what is/isn't/could/couldn't be done a few pages back:
Potential Urbanmech Variants and Quirks. I am also one who doesn't foresee the Urbanmech being a useless mech, and actually look forward to piloting one. I think in either attack or defend it will provide a decent screening mech to put surprising punishment on target while the heavier mechs take the hits . . . especially with whatever quirks it gets. On top of it, depending upon the quriks the thing might be able to take some serious hits for a 30 tonner . . . and based on the tiny, squat stature the thing might also be the smallest mech in the game, if not tied with the locust.
That would be nothing to scoff at.