loving the mod, mod do great with bob adjustable inserter if you never tried adjustable inserter, do it, do it now!
I am impatient to see more,
the chemical plant could be a 1x1 using the 4 sides
the refinery, can't see it smaller than 2x2
the centrifuge (should have been done)
small lab, steam turbine, heat exchanger, boiler, steam engine
pumpjack, solar panels, accumulators, roboport
rocket silo 1x1 would be amusing, to see small rockets
small turrets?
i use offshore pump anywhere mod, I could use 1x1 offshore pump but might get complicated. perhaps as submod(s) with other mod(s) requirement?
its not me being needy, just a "i l♥ve it, can i have more" kinda deal
you're the only one that i noticed doing this, dont give up!
the fact☼ry must grow.

Glad to hear you enjoy the mod! Although I personally prefer using Side Inserters (alongside my other inserter mod that cleans up the inserter menu) over Adjustable Inserters. As for additions to the micro machine list:

Centrifuge - This should probably be easy enough to implement

Chemical Plant - Technically possible, but it wouldn't look great (pipes wouldn't visually connect). I could maybe just limit the recipes to "one fluid input, one fluid output" only, and just add the two pipes in front and back. That could work, but might require a bit of effort on the backend for me.

Refinery - Would be nice if it were smaller, but I think the 3x3 version I use in Mini Machines is about as small as I would want to make it.

Steam engine/turbine, boiler, offshore pump, heat exchanger (basically anything with liquids) - I'm not sure how doable these are without checking, but maybe possible. I never liked shrinking the ones with pipe inputs though, because the inputs never line up properly with the pipes.

Lab and rocket silo - Would be rather difficult to fill these up from a belt, considering the variety of different ingredients required for the input. I do wonder what the rocket would look like though

Solar panels and accumulators - I think other mods add plenty of these, that there's no need for smaller versions. After all, why have a 9 t1 solar panels, when you could just have a single t4 solar panel that provides more power?

Roboport - Same as above, but also, it might look weird to have these flying bots that are bigger than the roboport they're all charging from.

Small turrets - Probably doable, but I'm not sure what the demand for that would be. These also tend to have additional tiers by other mods, that would be more effective than smaller turrets.

For the most part, the only thing holding me back from adding more of these micro machines, is the inventory/crafting menu cleanliness. I mean, I made an entire mod basically dedicated to sorting the inserter list (depending on what other inserter mods were installed as well), so any additions have to keep that cleanliness in mind. But I'm not entirely against adding more, if the demand is there.

And lastly... more like "The factory must shrink" lmao.

i have over 70 active mods and growing till it breaks, the need for cleanliness and prettiness or looking weird is looonnng gone
my factory has no belt [laugh in 100000 modded bots] no issue with small labs, rockets or others.
didn't know about mini machine, thx, but yours are smaller (micro smaller than mini) and therefore better.
tho I will take the refinery and chemical... NOT, because there's error with yours? probably not.
probably because of another mod in my mods spaghetti, not a problem, don't overthink/worry about it.