TLDR: You absolutely want as much/many axes as you can afford. KB/M does NOT cut it for proper flying. Handheld controllers for consoles, KB/M for FPS, and sticks for flying. This is the way.
OK, long/full answer here from someone who has spent a LOT of time flying with a LOT of different configurations, but without going down the full Simpit rabbit hole:
1.) Low budget - A plain ol' Logitech Xtreme 3D is still just great. You won't get a whole lot of buttons, you'll still need to hit up the KB frequently, but even this $30 investment beats the pants off trying to point a ship with your mouse! Won't last forever, Amazon says I've purchased 4 of them apparently, and my first certainly was bought before the Zon branched out from just books. Still my go-to stick for Star Wars stuff like XWA or Squadrons where fewer buttons are needed:
2.) Low-Midrange - The Logitech X52 served me very well for a long time in Elite/SC, and my brother still uses his. Great point to dive into two-handed flying. Other contenders here are the cheaper TM T-Flight, though I find this one a bit TOO simplistic if you're bothering to go HOTAS. On the other end I think the X-56 is a bit too big of a price jump over the X52, and the T-16000M throttle was just plain to HUGE for my not-very-huge hands.
3.) High-Midrange - The most recent addition to my collection is the new Omnithrottle from VKB. I shied away from HOSAS until this baby came along, so that now I can FINALLY have translational axes on the LH that make SENSE! Twist-axis-for-Z-translation was just too weird for me to be willing to take the plunge, but the Omni fixes that problem, and so far I'm loving it! You're approaching the $400 mark now for a set of Gladiator stick + Omni, but they're good pieces and arguably worth the price:
We sell VKB Flight & Space Simulation Controllers for customers in the United States and Canada.
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4.) Top-of-the-line - For YEARS I lusted, and finally about two years ago I took the Virpil plunge. We're talking $800 territory now, but hey, that's still only half the cost of that new RTX 3080, right? The Virpil stuff is just knock-your-socks-off amazing and beautiful though. Everything is machined and anodized aluminum which won't only last forever but the attention to detail makes them as much pieces of art as they are controls. For airplane flight simulators the controls on the throttle will basically cover everything you need to fly a jetliner. For space simming, the Constellation stick has some really nice features like the flip down trigger and analog ministick which come in handy for all sorts of things. Not the sort of hardware you just buy without a plan and a certainty that you're going to use it a lot, but creates a nice feedback loop that just looking at it hanging off my desk makes me want to fire up a game right now just to use the thing!
★ Aircraft-grade Duralumin Mechanics ★ Adjustable Finger-Lift Detents ★ Dual Throttle Axes ★ Analogue Slew Stick ★ Programmable LED Lighting ★ VPC Contactless Digital Proximity Sensors
virpil-controls.eu
★ Right hand variant ★ Metal Flip Trigger and Brake Lever ★ Material - Enhanced PU Plastic Construction ★ Flip trigger and dual stage trigger can be activated simultaneously for additional stages ★ Digital Brake Lever Axis ★ All-Metal Twist Axis Mechanism with Lockout ★ Adjustable hand rest...
virpil-controls.eu
★ Compact Design for Desktop Use ★ Dual-Cam Per Axis ★ Aircraft-Grade Duralumin Gimbal ★ Swappable Springs and Cams ★ Compatible With All VIRPIL Grips and Thrustmaster Grips
virpil-controls.eu