I can't stand mortars, they absolutely ruin matches. On one hand, I can't entirely blame people for using them, as they can be total game changers, but really, I tend to look down on people who do use them, you're not a real competitor if you're relying on them. I'd love to see them removed completely, or just nerfed outright, I couldn't really care less if people who use them have an issue with that. That being said, I got a feeling the type of people who use mortars are whiny brats who would flood plarium with their tears if the only weapon that makes them appear to be decent got nerfed or removed, so I'd say the best option would be to set up mortars to hit with friendly fire. Leave them as strong, but if you're going to use them, you're going to wipe out your own team in the process.
I absolutely agreed with EM rifles needing to be nerfed, until I got them myself. They require some level of skill, a miss, especially on a close target, can break you, and facing off against an opponent who also has them becomes a race to who can take who down first, plus they can be a real equalizer against certain mechs, such as lancers or tengus that have jumped up to a spot that isn't easy to hit.
I'd rather see javelins or disc launchers get nerfed over EM rifles, especially the damage radius on them. With damage radius implants maxed out, the distance that they can have an effect can make them as bad as mortars. Really, anything that removes the need for precision, and in turn, skill by the player, should be nerfed.
As for zephyrs and surges, I don't really have an issue with the pulse effect, it can be annoying to get hit with, especially if there's multiple mechs in the field with them, but both mechs have fairly low hp, so they're still a liability, and the zephyr is slow, so that one is even more of a challenge to work with, pretty much only effective if you can find a decent spot to pin up in a lock out the other team, and that still only tends to work for so long before you get rushed after a pulse. The part with the surge that I'd like to see changed is the stealth buff removed when it dashes, just leave it with the dash and pulse. I'd also change it so the surge and killshot get hung up by panther's barrier. As it stands, they can just rocket through it, they should be held up like any other mech.