I love the overall atmosphere, this is one of my favorite genres too!

The bell lead quickly gets tiring though. I think it might be the release on the bell or maybe the reverb. Shortening the reverb would probably make the bell sound a lot less muddy. I think starting with low release on the bell for the first few bars, then transitioning into the normal reverb / release levels would be a cool intro effect as well as ease the repetitive nature of the bell melody into the listener's ears.

Decreasing the tempo around 00:58 might sound good as well, in addition to giving the listener a break from the bell.

I might also try to change up the bell melody a few times throughout the song, but only in little ways (maybe a note or two), so that the melody piques the listeners attention a little bit before lulling them back to sleep (Someone might hear the change and be like "ah! that's cool"). At least once in the first minute would be nice. 00:47 sounds great because of the tiny break from the bell! -- maybe more of this?

The bass starting at 00:10 and transitioning to the main bass at 00:19 is a great transition and sounds really good but the instrument sounds a little basic (I don't know how to describe this, but it sort of sounds like somewhere between a saw and square wave with the high end filtered out). If you could somehow give it a little bit of personality in some places it would sound better. Maybe a tiny bit of distortion or overdrive?

The drums are like this too. If you could take each sample and give it a tiny effect like playing over it a (very quiet) bit of a random sound effect or a phaser. It would make the song sound a lot more polished.

You're only using a few instruments, so each one has to be special -- each one has to have it's own unique flavour!

Nothing wrong with the composition of the drums but it feels like something is missing. Maybe some of the beats are off a bit? Maybe I'm going crazy? I don't know, but double checking it anyways once more can't hurt.

The strings note at 1:41 sounds a little too high and the note after it also sounds a little boring. Maybe look for some more flow-y notes by changing the pitch a bit.

The ambient sounds and french voice both really fit the atmosphere. Good sound design with them too!

Summary:
Great atmosphere but is repetitive and lacks a unique 'flavour'.

If you could tell me a little bit about how you made this song it would really help me to learn more! Love it!