Which new advanced systems were installed on the ship besides the upgarde to pantsir and the change of the strike missile complex?
Presumably any floppy drives and HDDs will have been replaced with solid state drives and the copper wires likely improved with fibre cables and modern processors and modern computing equipment.
The single purpose SS-N-19 Shipwreck missile launch tubes and SS-N-14 Metel anti sub anti ship missile launcher has been replaced with the UKSK universal missile launch system and presumably the S-300F system will have hopefully, its rotary launch system that was large and bulky replaced by fixed cells carrying rather more missiles as well as the S-350 missiles and perhaps also the improved naval Tor system with new missiles have been installed too.
The scope for new radars and new sonar equipment and new EW equipment is rather broad, and presumably they have probably expanded their options for helicopters... including, but not limited to Ka-52 and Ka-226 types as well as the new helicopter to replace the Helix which presumably if not seen on the upgraded Kirov class ship might be shown on the new helicopter carriers.
They might retain 30mm cannon, with air burst shells for anti drone use, but equally they might have added 57mm gun mounts for extended effective shooting range against a variety of air and surface targets.
By fitting multipurpose launchers of the UKSK and Redut type they essentially future proof the design as new missiles will be designed for these launchers.
New AESA radar and EO systems should improve performance and situational awareness.
The AK-130 seriously lacks range though it is not a terrible gun.
Longer ranged ammo could be created but I suspect joint work with the Russian Army on new long range 152mm rounds makes rather more sense for both parties wanting accurate long range rounds.
Further down the track a 203mm round might be useful for both forces to add further payload and range without making the systems huge and expensive.