nice use of the kirins and I think this will be a nice idea of him

Not sure a you will make up for everything, but it's a start at least.

The first place he went to was the laundrette, where he found several tables of ponies (and in some cases kirins) sorting through mountains of clothing. Putting them through a series of machines that did all the washing and drying for them, the kirins would then put on some kind of horseshoe with a strap and flat metal edge and use their powers to heat it up, flattening the creases.

I just had an idea:
Can kirin (or nirik) create enough heat to supplement or even replace the generator?

Drill didn’t realise it but a smile had crept across his face as he disrobed himself, giving his clothes over to the staff to be washed.
Part of him shuddered at considering how dirty said clothes were given the previous day.

"Don't worry, in comparison to most deep coal miners your stuff is basically pristine."

He brushed the thought aside and knocked on the front door, at first he heard nothing but right as he was about to knock a second time, several increasingly loud, frantic hoofsteps signalled the presence of sompony not just running, but galloping towards the door.
He took a cautious step back just in time for the door to swing open, narrowly avoiding being smacked by it.
The cherry red mare on the other side had just enough time to spout- “Hi there how are you doing I’m-” -before the door bounced off the wall and back into its frame, likely slamming into her in the process.

*muffled by the door* "Ouch! My poor muzzle..."
Reminds me of the scene with Sprout and the door from the G5 movie.

“What age do we live in that kids don’t get toys…” And it was at that exact moment that Drill had an epiphany. “Wait, wasn’t Toy Chest a toymaker before the frost?”
Drill immediately snapped back to Rose Symphony with a grin.
“I think I know how I can make it up to Comet!”

Open a toy factory and let the kids work there?

Good chapter!
I enjoyed reading it.