I actually play Seraphon as my other army and this is a bit misleading.
Salamanders are definitely super good, short range not withstanding. They are in the same ballpark as stationary Leadbelchers though.
Kroak honestly is very good at hero sniping due to his ability to aim mortal wounds around, but he wouldnt have the best matchup vs. Ogres. His abilities spread out mortal wounds at a high efficiently against multiple units (which is why he is good at sniping characters), but would seriously struggle vs. big Ogre blobs where you have 3-5 huge wound soaking units. To optimize Kroak, you also need to also spend another 300pts+ on support, like a banner and Guard.
Seraphon are a super weird rock paper scissors match-up for Mawtribes bc the Coalesced 'take 1 less damage per attack' probably hurts us more than any other faction due to our prolific 2d attacks, but I think we have a great matchup vs. starborne, and leadbelcher / frost sabre lists dont really care.