My other little thoughts:
Changelings are pretty much immortal unless they're killed.
They CAN reproduce if a dying Changeling is absorbed by a healthy one. It gestates for awhile and separates again once it can survive on its own. It starts over as a baby, but with all the knowledge it had previously. Essentially it's like a Phoenix* and it only happens if the population drops below a certain number.
Changelings have quite a bit of genetic diversity, and that determines their "default" humanoid form**. That's how I explain why they all don't look like exact copies of Odo. They can choose which gender they want to appear as and they can pick their hair and eye color if they want, but their body shape and facial features will always have some variances. (I hope that makes sense lol).
*I had this happen in my For Freedom's Sake fic, where the baby Changeling from The Begotten absorbed itself into Odo. Except it was so sick by the radiation that killed it that it used a lot of Odo's DNA to reconstruct itself, so as a result it literally became his offspring, and Odo developed maternal instincts towards it while it grew inside his body. My avatar is a photomanip of that baby after he grows up. Odo named him Kejal. Kira was with Odo when he had Kejal. Kejal and Odo linked during the birth; Kejal pretty much felt how much Odo loved Kira. Kira and Odo were the first faces Kejal saw, so when he could take humanoid form **he ended up looking exactly like his mother, but he chose to have Kira's hair and eye color because he wanted to "look like how much Odo loved Kira." He does call Odo "mother" and Odo doesn't mind. Doctor Mora Pol is "father" since he is the one who raises Kejal in secret. (Odo gave Kejal to Mora when Kejal was just a newborn because he feared the Founders taking him away and punishing/corrupting him. He made Mora promise not to experiment on him and to let him go if he wants to find Odo when he grows up, and Mora kept that promise. Raising Kejal was very healing for Mora, as it turns out, since I firmly believe he regrets driving Odo away. I've got ideas about Mora's past and his motivations to raise Kejal right, but we'll be here all DAY if I start into that!)
Oh God, I'm rambling about my own little fanon aren't I? I'll shut up now.