I don't think I've actually seen a situation where the Clan RAC's slightly increased bulkiness actually makes a difference, especially in light of basically every other Clan technology being less bulky than the Spheroid equivalent. Also wish that the Clans and IS had their own versions of both Plasma Cannons and Rifles, but that's just because I'm a bit of a plasma buff.Thing is, the ER Small's BV is so much higher is because it's double the range, and honestly it's well deserved. 2/4/6 may not feel all that different to 1/2/3, but it really is; there's just so much more wiggle room with the 2/4/6 to get into that woods for an extra to-hit modifier, reach out and touch a BA suit, stay just outside punching and kicking range, put yourself in just the right position to block LoS of another enemy Battlemech to keep you relatively safe...
That, and the peculiarities of BV means that weapons with an inherent to-hit malus (MRMs, heavy lasers) are somewhat over-valued in the BV calculation, while weapons with an inherent to-hit bonus (Pulse lasers, LB-X clusters) are under-valued, so the Heavy laser isn't really all that great for Bang-for-your-BV either.
You're telling me about the over valuation of MRMs? hahah...yeah, I know all to well. Don't get me started on vehicles either... ;D
As I said in my original post, if we are ignoring battlevalue and setting the game up some other way, or just looking at it from a fictional standpoint, the heavy small's value is minute when compared to the ersmall.
When it comes to the game, regulated by BV, that is when the heavy small shines. I have had no issues using a firemoth H to carve people up. I have also used it to scare the heck out of some players. Its nice to stab another player's mech in the back with all of those heavies, but forcing them to make a mistake or to stay out of an area allows a player to control the other. Is it harder to hit things with the heavies? Sure, but I'm sure I mentioned that already and that it takes extra work to do so.
Thing is that some players simply do not have that extra mental capacity to use 2 Firemoth H's over a Firemoth with er smalls. You need to be far more calculating with the heavies as you need to know the target, know what weapons it has, what it's friendly units have that could pop the firemoth, know how much MP you have to use, and where the target is likely to go. If you know how to force the initiative that also helps, by that I mean force someone that won the initiative to commit to moving the target unit early in the turn in addition to it's likely supporting units. This helps to avoid the need to roll higher then the other side, which is something I cannot rely upon. Some players can take an hour to make a single decision and will if you let them, those are the kinds that should not be using the Firemoth H. If they do, they should expect it to get popped with ease. Personally, I like to keep mine intact to continue influencing the other player and to stab them.
Getting 2 Firemoth H's for the price of one with er smalls is well worth it since I know that I can make use of them with ease. That's twice the influence and twice the stabbing power. The funny thing is that people think that using the Hs properly is easy enough, so after a game where I have used them they decide that they are going to return the favor. The last time that happened they brought a pair of H's as part of their force while I had 2 Spiders in my force. They wanted an assault to shoot in the back, so I gave it to them, but just far enough that they would have to shoot at it 3 hexes away. They missed with most of their shots on the front. They met my spiders who started putting holes in them. Next turn I pulled my assault back towards a Zhukov with AC10s loaded with precision rounds. The Dasher H's had to move away, but my spiders were able to keep up with them thanks to terrain eating up their MP and my Jumpjets. My spiders stayed on them, but in their long range bracket. They tried to mimic what I had done to them, but failed to realize how much MP they needed to be effective. They didn't watch for my counters. They failed to have a position to fall back to if they got mixed up with my lights, something similar to having my tank sitting in woods with precision rounds that could rip off any part of their Dashers. For them it would have been better to use a firemoth with er smalls, but even better if they used the D with its er mediums. The lack of experience got their Dasher H's decimated with ease, only landing a single shot on my spiders before being put down. In the previous game I knew what I was doing with my Dashers. Without experience a pair of H's cost them 1.5k BV with very little damage done to my units. In the previous game I had used 1.5k BV and killed a few units with them and influenced the movement of other opposing units making the BV expenditure well worth it. If I had used er smalls there wouldn't have been much of a difference other then I would have 50% of the available damage potential of a pair of H's. The 1.5k BV for an er small armed dasher would have actually been a loss of 50% of that BV wasted on making things easier for me when I didn't need it. The other player would have gotten at least 750 BV points worth of value out of the suggested er small variant, instead they got zero value out of the 1.5k bv spent on a pair of H variants. It really does take a greater amount of foresight and attention span, but if you have it then the Dasher H variant is the way to go. That's not an insult being hurled at the other players I have played against in the past or currently. It comes down to knowing what you are capable of, accepting it, and working to get the most out of it while working on getting better. Unfortunately, it seems that players now seem to be unwilling to talk about the game afterwards and less likely to ask questions about what they did wrong, or could do to improve. Instead they seem to take insult regardless if things are sugar coated or put bluntly just the same.