Larger size, bigger cabin, superior layout and that's just what we can see from preview images
But that model doesn't look like it has a bigger cabin and so the layout is the same with a slightly different tail fin configuration... in fact I would say that model is smaller than a Ka-27.
Ka-27 is way past obsolete
Have never heard any complaints about Kamovs to be honest...
Looks kinda like a Kamovised Mi-38.
The Mi-38 is way bigger... this model looks smaller than current Ka-27 models.
Modern composite airframe & rotors, new gen engines can be a big improvement over Ka-27 without needing to be a fully exotic design.
The Helix already has composite rotors and new engines... I rather suspect the replacement for the Ka-27 will be slightly bigger but with more streamlined aerodynamics for higher speed flight.
Why move forward when you can scrape along on past trash?
Why spend vast amounts of money on a brand new pen when existing models already do a good job.
If the older aircraft were rubbish there would be much more focus on their replacement...
So speed, payload, range, endurance, cargo ramp, internal space are all irelevant as long as they have something that can stay in the air and look borderline useful?
The speed range payload endurance and internal space of the Helix family are already much better than the aircraft they replaced and compare rather well to foreign models... their coaxial rotor makes them easy to fly and much safer on deck than any design with a tail rotor design.
Why bother with Su-57, Gorshkov, T-14 and all that other stuff when MiG-21, Grisha and T-64 can be upgraded?
They don't have unlimited amounts of money and resources so it makes sense to replace things that NEED replacing first and the Helix already does a good job so the replacement for it is not overly urgent... it is being worked on but hardly a priority.
It doesn't have a cargo ramp, you can't put anything inside it larger than a person
It is a SAR, plus an AEW, plus a troop transport, plus in on version it was used for long range guidance of very long range anti ship missiles... WTF would they need a cargo ramp for?
If that airframe isn't shaped for a ramp I dunno what is.
If they wanted a ramp they could easily have had one.
If they make the replacement bigger... it wont fit on any of their existing ships because they were all designed for Helix based helos or smaller.