I do like some features of this but I do also disagree with some for example
Disagree:
Removing stings - This is something really helpful for the ling and honestly is just genuinely helpful
Making them have less lives - I think this just takes away from the spooky vibe of the changeling, making a monster kill able makes it seem weaker, and likely to be meta rushed. By that I mean, security won't care for there lives and the ling is likely to run away making them loose the big scary monster and loosing the strength you wish them to gain.. (i think lol)
'meh' : The infection, which is one of the main parts of this conversion ( well at least I think it is ) While I do think its quite a nice change to the changeling and allows new scenarios I feel like just 'slashing' someone is quite OP and should be replaced with an ability where the victim must be downed and stung or something along them lines.
Summery of infection:
+ Gets the entire crew evolved, no one is going to be left out if murderous monsters are on the station. Or if there life is threatened by a fucking disease
+ Could lead to interesting scenarios, quarantines, the sacrifice of masses. etc lol
- Slashing infects, I just feel that could get /very/ out of hand quickly and just a mess rather then RP.
Agree:
Some of the new abilities you have listed seem quite interesting and have some good depth to them.
The focus on the horror form seems pretty neat, making the changeling seem like a bigger threat and puts a better focus on the crew working together to take it down rather then sec memeing it with a harmbatton.
Suggestion:
For the love of god an ability to open a broken door with powers or something along them lines. no one likes being stuck in solitary. /NO ONE/ does.
OVERALL:
Some ideas in this are pretty neat and I do like the direction this suggestion is heading, obviously its not perfect, nothing is but its a start
Anyway +1 from me there just my thoughts