That's my thought as well. The large blazer only does 50% more damage, which is why I went with 7 damage but even that would be a massive boon for light mechs. It would also be the perfect counter for those pesky Clan medium lasers when Revival comes around.
No, I meant blazers. We all know that Heavy Lasers are what Blazers want to be when they grow up.
7 damage is probably too low. Even using the "50% more" from the Blazer, I'd round it up to 8. Doing 8 damage on 1.5 tons would be playable, I think, even with that high heat. Bugs would probably like that a lot, whereas at 2 tons I'd just take the two MLs on a Spider.
Ignoring weight/slots for a second, I think the Blazer might arguably be a better weapon than the HLL. 16 heat and 12 damage vs 18 heat and 16 damage(at +1 to hit)? Not an easy choice, tbh. The Blazer has BV 222, while the Heavy Large is 244, so statistically (using the base BV math assumptions, which probably under-penalize to-hit penalties), they're nearly equal in actual damage dealt. The HLL wins on the five tons you save, obviously, but otherwise they're not too far off.