I fly exclusively micros. My favourite format is a 2s, 2.5 - 3 inch toothpick. This time I wanted to build something 1s, that would perform as close to that favourite type of quad of mine.
I have a 1s 3-inch Baby Tooth and I don't fly it much - it feels too underpowered and floaty (big disk surface, small weight).
Knowing how phenomenally a 2.5 inch 2s can perform, I decided to try this prop size for my project.
The biggest challenge turned out to be the motors - for a 1s 2.5inch build I wanted an 11xx - 13xx 14000kv+ and I have quickly found out that these motors are super-hard to find... There used to be a number of such motors in the past (Betafpv 1103 15000kV, Diatone Mamba 1103, Geprc 1102 14000kV and others), but these days, the only remaining option is Betafpv 1102 18000kV. It utilises 3-hole mounting with thosr strange 1.6mm screws and push-on only props (no prop screw holes). There is a limited choice of 3-hole frames...
Luckily for me Quad 66 was kind enough to combine his two frame designs into one (Sky Rider and War Pig - I proposed the name of Sky Pig or War Rider for the hybrid frame, which was perfect for my needs - for this he's got my deep gratitude!
With these obstacles out of the way I could start gathering the components:

Frame: Quad 66 Piglet 2mm,
Flight Controller: Flywoo 1s AIO with built-in 250mW VTX
Camera: Flywoo nano camera (looks to me like a re-branded Runcam Nano - I'm not sure which one, because I normally use Caddx Baby Ratel in my builds - in this case I needed something super-light)
Canopy: 3D printed Flywoo,
Motors: Betafpv 1102 18000kV
Props: I keep alternating between HQ T65 Durable both bi- and tri-blade as well as Gemfan 2512 tri-blade, depending on mood or current PID tune
Rx: ELRS EP2
Batteries: GNB 600mAh HV (yellow label)
Hardware: plastic bolts and nuts
PowerConnectors: BT2

How does it fly? Well - I am still fine-tuning it, but it already flies way, way better than my Baby Tooth 1s. It is more manoeuvrable, handles wind much better and overall is more in line with my 2s builds.