I have a 2000 model Honda XR250, and it is time to update.

I am thinking about a 2004 XR400, due to easy to service, change spark plug, easy kick start, and no battery or coolant to be concerned with...

Or should I bight the bullet and get a late model Honda CRF450, or KTM 450EXC. But this increases service issues... Or is the power, handling, suspension improvements worth it?

i guess it depends on what sort of riding you're doing. if you're going hard and doing some semi serious racing then yeah: go for the later model honda or the jewburner bike.

but if you're going out for a weekend away riding with your mates i would go for the xr. easy to work on, no radiator, you can get parts at the local milk bar, and they are built a bit more solid than the crf and ktm.

My riding style is Dakar with some Longboard Cruise thrown in.
Typical ride;
15km of bitumen
Special Stage, 30-60km on gravel, sand, sandy gravel, and very short bursts of rock and water, and I usually always dodge the water to keep the bike clean!
15km of bitumen home

On the special stage I will always stop for water and a rest!
But the bike must be set up, 100% for The Special Stage.
I just ride solo, when time permits. I've done about 5,000km on dirt with this bike out of 11,500 on the clock. Only laid her over once on sand doing 5km/h, and dropped it in the driveway once and it bent the clutch lever perfectly into a 2 finger lever. Super light clutch, so I was really happy with the end result!

Have a mate that has a great condition XR400 for sale.
Local too.

PM Sent.

what about a dog rooter? (DR400)

Hi mate, I road XR400's for about 5 years living in kalgoorlie. The loved the enduro stuff. Bulletproof too. While all the KTM, EXC and WR rides were doing post race filter cleans and checks at night on the 2 Day enduros, I was kicking back drinking beer as I knew the old 400 would be right to go, even if I did nothing.
Cheap to get bits for, reliable workhorse and surprisingly competitive.