--"Do I need Mini Machines?"
Nope, it should work perfectly fine with or without Mini Machines. The only hard requirement is the Factorio Standard Library, located here.

--"Mod compatibility?"
If the other mod adds assemblers, furnaces, miners, beacons, or radars, and is not on the list of compatible mods, then it most likely will not be compatible. But for most cases, I can probably make it compatible, so please do not hesitate to ask. Any other mods that don't affect the above listed machines should be perfectly compatible.

--"Balancing?"
It's most likely overpowered, but it's also kinda supposed to be. They're just really hard to balance properly, so I decided not to, and just made them more expensive. They have the same crafting speed and energy requirements as the base machine, but in 1/9 of the usual space.

Micro beacons are probably the most overpowered, as they are smaller and have the same effectiveness and range as the usual beacon, so you can plop them down almost anywhere. Micro furnaces are probably the second most overpowered, as their recipes only require 1 input and 1 output, and they can be placed in the usual smelting patterns (in much less room). Micro assemblers have the annoying drawback of only having room for 4 input/outputs, which makes them less useful for belt blueprints, or high demand recipes. Micro miners have a fluid drawback on uranium patches (only one fluid input which can't be shared directly to other miners), but they should work great on all other patches. Micro radars are probably the least overpowered, as they just take up a little less space than their original counterparts.

There are options to disable any of the micro machines you do not wish to use, or to increase their crafting requirements (up to 5x the original machine) so they won't be as easy to spam out.

--"I want to do my own micro machine balancing" (for other mod makers)
As of v2.0.10, my mod will detect pre-existing micro machines, and make no changes to them, allowing the other mod to handle the icons, balancing, recipes, and tech requirements. In order to be detected properly, the name of the tier 1 micro machine must be in the format of "micro-machine-type-1", where the "machine-type" must be named: assembler, furnace, miner, beacon, radar for vanilla.