Howdy! Yea these are some really solid ideas to be fair, I like the angle your taking.
The stone replacement is intriguing ... I like the concept for calcite, to remove the need for an orbiting platform or pre advanced asteroid processing. I would be hesitant to replace stone entirely however... that definitely deserves some more consideration! Keratin from stomper shells has crossed my mind as some sort of rare and difficult to farm resource to try acquire in the past, and this is similar to this in some ways.
Regarding the others
Gleban Inserter - neat concept, but I don't know if I would want my inserters to run on nutrients too? unless they had some insane stats perhaps...
The idea of bio-variants is definitely something i have already considered too - the idea of taming pentapods, to make turrets or just your own little wriggler army to bring back to nauvis would be fun, and they could run on bioflux as a fuel source.
One of the plants, I think its a lickmaw or funneltrunk, has a bunch of branching root systems that could be repurposed into some sort of collider-free electrical grid object perhaps.
Radar replacement is certainly novel... I wonder if you could have some sort of nest of pentapods that send out search teams too.
I also really wanted to have an alternative to bots (particularly nice for Gleba starts) where the little wrigglers carry your items between nests. (cute as hell)
Thanks for the post - I really appreciate discussing neat mod ideas and it helps feed into a bit of motivation to improve my current mods and continue making new ones!