Yeah it would be a lot of work, but I never see that as an argument against an idea. It’s a games studio, all they do is make games non-stop. It’s literally their job. We as the community should never ever dismiss an idea because we deam it to be too much work. It’s not our place to decide that and it’s something I see mentioned on those forums all too often.
As for tech mage or similar…I’d personally 100% prefer a Ratling over any form of new human sized archetype. We already have 3. Let’s have something as different as an Ogryn in the mix. Exclusive weapons etc can be applied to anyone, just like they do with the current archetypes. Why can’t a vet have a flamer? Because reasons.
I think a Ratling would be huge fun. Obvs just my opinion and preference but the unique things a Ratling could bring to the gameplay and approach would be brilliant and fresh.
Edit: on the topic of new voice lines - that’s actually not insane amount of work. The sound designer would do that on his own steam and it’s a case of getting lines approved then having a few recording sessions. They’d record a load too and have a catalogue to use. I’m pretty sure they added quite a bit of new adio/VO on the last couple of big updates