I would go

Mono Synth – Think of it as an instrument that replaces your guitar.

Next Dirt – Low gain to high gain for stacking.
Grunge
Death Metal
Tone Tattoo – Tone Tattoo last because it has a built in gate for djenting and has the Memory Toy at the end.

Expression Pedal

Canyon

It’s most common to put your expression pedal before delay so that the delay will repeat the swells of the expression pedal. If you put the expression pedal after your delay, then you’ll be swelling the delays. That’s cool too, but try them out to see what I mean.

Some people put their expression pedal before their dirt. That would be kind of like turning up the volume on your guitar to control the amount of distortion you get, so not swelling the volume really, but the gain if you know what I mean. You’re clearly a high gain super compressed kind of guy, so you’ll probably prefer your expression after your dirt to get those violin/cello type of sounds.

Most people put their time based stuff (delay/reverb) after their dirt, but My Bloody Valentine and other Shoe Gazer types would sometimes put their delays and reverbs BEFORE dirt just to really jack things up. The dirtier the better as far as shoe gazing goes, so they would just put everything before the dirt and see how hard they could push it and still be able to make out the notes they were playing.

I would put it either

Mono synth
<--- here
Canyon
Death metal
Grunge
Tone tattoo
<--- or here
Expression

I don’t think it makes sense before the Mono Synth because it has its own mods and the Mod 11 might interfere with its triggering anyway.

Modulation before a delay causes repeats of the modulation. Modulation after a delay cause modulation of the repeats…completely different.

Volume modulation before distortion causes a GAIN modulation in the distortion. It’s like using the volume knob on your guitar to go from clean to dirty, to clean, to dirty…

Phase, Flange, Filter modulation before distortion is much more subtle than after distortion. I think the majority of people prefer phasing, flanging, and filters like wah BEFORE distortion, but I don’t think it’s a huge majority. I think maybe 30% or more prefer those AFTER distortion.

Volume modulation after distortion makes the distorted signal change volume WITHOUT going from clean to dirty to clean to dirty. You can have a fully distorted, high gain signal pulsing in volume.

If you plan on using any of the dynamic modulation capabilities of the Mod 11, like changing the rate or depth of the modulation depending on how hard you play, you’re better off putting it in front of anything that compresses your signal. Heavy compression eliminates changes in volume. High gain metal pedals tend to be heavily compressed. So, for instance, if you had the Mod 11 set to change the rate of the flanger depending on how hard you play, and you put it after your Death Metal pedal cranked up all the way, you’ll notice that the rate won’t change when you hit it harder. That’s because the signal is heavily compressed. If you put it before your Death Metal cranked up all the way, you CAN control the rate of modulation, but it will sound different.

This is really one of those pedals that you’re best bet is to play around with it in all positions and see what you like best, but there will be some trade-offs compared to have separate mod pedals that you could put anywhere in the line.

Still, whether you’re a mod before dirt or a dirt before mod kind of guy, I think you’ll end up either between the Mono Synth and the Canyon, or between the Tone Tattoo and the Expression pedal. I think those two spots give you the most control over your sound.