Balance bike.

Early rider is as good as it gets. Hornit Airo is also excellent and far cheaper.

And choose between being lightweight or having a brake. For a little nipper, I think lightweight is more beneficial. Others will be along soon to disagree.

Save your budget for the next one I’d say! Strider 12 or vitus make excellent balance bikes for half that budget. Put the saved cash somewhere safe so you can buy them a decent pedal bike at the right time, that’s when a) a decent budget makes a difference and b) being tempted to make them wait cos you can’t afford the next frame size up sucks.

How old is your son? Just for comparison we had 2 cheapo no brake £25 ones from Halfords (twins) tried them at 18 months and they didn't really get it, another 4 months later at 2 they really got to grips with them in a couple of hours, from Feb this year till around June they loved them and were on them most weekends, they got to the point they'd run on it, slot their feet into the bottom of the down tube, then swoop around side to side, tbh they rode them to death, to the point both headsets were shot, at that point after 6 months it was buy another B bike or find two small Frog pedal bikes. They were peddling the Frogs after an hour and never looked back.

All kids are different but I'd echo the above, cheap balance bike and put the money aside for a good pedal bike.

The whole experience/development is amazing fun though, enjoy.

In contrast to the above, at first we paid £40 for an anvil with wheels from Halfords, and it didn't get much love, and was a bugger to carry. The much lighter hornit was money well spent imo.

£200 is maybe more than you need to spend, though.

buy a cheap one. Its a balance bike for god sake. Go to halfords or decathlon.

https://www.chainreactioncycles.com/p/vitus-nippy-superlight-balance-bike?color=silver&sizeStandard=10%22+Wheel

Get used Strider off eBay, use it some more, sell it for same money you paid for it 👌

Ours was £25 from the middle of Lidl. He's been using it almost every day since he turned 2, 5 months ago. He loves it. I'm not sure what more you need for almost 10 times the price.

I'm a fan of the Kokua Jumper. Very light, comes with short and long seat post.
Good value second hand as not too mainstream but have good parts availability from UK distributor.

My two pennies on weight, look at it as a fraction of their bodyweight, would you look forward to riding something more than 50% of your bodyweight? A mere kg gain could be 10% more weight.
Also remember that you/your partner/your parents may well have to carry it when they get bored of it mid adventure.

Don’t spend £200 on a balance bike - it’s just 2 wheels, a frame and maybe a back brake. Depending on size the Halfords Indi for £25-£30 was good just to get our daughter into the idea of bikes.

Then we moved up to a Wiggins Pau - genuinely a lovely little balance bike. Light alloy frame, v brake on the back and 12” wheels that roll fast. She used that so much during Covid lockdown. <br /><br />

Only started spending more once we looked for a pedal bike - went with a Cnoc 14 then. Equally the equivalent Frog would have done the job and the Carrera Cosmic / Pinnacle equivalents looked decent for the money 

My 4 girls all pedalling before they were 3. Had a mix of BB, decathlon model did the job, but a pair of very old Rothans were heavier but much better once serviced. Look for semi slick pneumatic tyres, bearing headset and proper v- brake with small lever.  IMO those things make a difference for progression and fun, lots of options to suit any budget now.

Strider worked great for my two. We did eventually have to replace a wheel as a steep 350m gravel driveway wore it out!

Started without the brake and then added it as they got older. Passed it on to neighbours who had two kids as well.

Stealth ad, I have a frog tadpole mini in green. PM me if interested.

Banana bike GT.
As light as any balance bike needs to be, with proper bits on it
Cost £45 from Amazon when we bought one for my daughter.

She's now 8,on an Orbea MX20 but still occasionally trundles round the garden on it 🤣
Need to get rid.