What steam loco.improvements should Lionel and MTH work on.

Making them as Gomez Addams proof as possible.  Or at least as robust as the early 1950's stuff!

Bulletproof electronics including motors.

1. A modest gear ratio for ~70 scale mph top speed.  Most of us don't have layouts that support 100 mph operation, and there are already plenty of fast locos already out there.  (The Bachmann Ten Wheeler is a good example of a modestly geared loco.)

2. Replaceable wheels and axles, including a set in the box WITHOUT rubber tires.  [It's interesting that MTH designed their HO locomotives with a removable "bottom plate" from the very beginning.  It chagrins me that he hasn't retooled his O gauge offerings to conform ]

3. Flywheel coasting action.  IMO, too few late-production locos have the sense of momentum like their 1950s predecessors.  This also makes them more forgiving over dirty track, etc.  Lionel has started using "back drivable" gears (wheels can turn the motor), which I really like.

4. Make the above features available in "traditionally sized" locos that look good on O42 and O54 curves.

My $.02 (or is that $.04?)

How about some of the basics required for scale three rail running?

1. Scale couplers
2. Proper height off the track
3. Fixed pilots
4. Prototype fidelity

Agree 100 percent

Hello guys and gals........

PLENTY of replacement parts from ALL model train companies.

the woman who loves the S.F.#5021

Tiffany

4877:

At least you kept your GG1 tuscan!

I think one piece round boilers would be a great improvement.  Scale engine beds would also help, with the above-mentioned plate to remove drivers.  Actually, if each axle had two pedestal binders, it would go a long way toward making these fine models closer to the real thing.  Third Rail has pretty much done all that, so it is not impossible in 3-rail.

Please get rid of the rubber tires

Make something without a Bellpaire Firebox

I wouldn't mind a tether IF they would conceal it better and put a footplate over it.  I've seen the new MTH gizmo drawbar and it's a Rube Goldberg design for sure.  No way to backfit older engines unless they come up with yet another design.

Go to school on the 3rd Rail offerings.  Even though I just got my only 3rd Rail engine (E7) all I can say is WOW!!!  If 3rd Rail can offer a "standard" engine with as much individual detailing as they have on the E7 then MTH and Lionel ought to follow suit.

On scale equipment, lose the rubber tires, leave that for the 027 stuff.  Every engine I have is heavy enough not to need those tires.

Most coal burning steam locomotives needed a coal auger between the engine and tender, anything would be better than nothing. LIONEL, combine the dummy auger with the wireless tether.

Front working couplers on all steam engine not just choice models

And then making the high end stuff available in 2-rail.

They should both keep a inventory of parts incase repairs are needed.

I second this suggestion also

Blacken the shiny parts on wheels and valve gear.  (Some come this way, but not many.)

Probably the most offensive thing that needs correction is the pilot/pony/engine truck wheels being undersized on 3 rail scale steam engines. 

MTH needs to substantially improve the quality and variety of their steam locomotive sound. The chuff sounds on my Premier NYC Mohawk 20-3372-1 are anemic and I cannot get MTH to re-issue an improved version because "there are not enough complaints."

The quillable whistle leaves a lot to be desired. I don't waste my time with it. 

Lionel's quillable whistle is outstanding.  Admittedly, all I have is the PM 1225 but it has been a great engine.  When I voiced my only (minor) irritation with it at a club meet, I was gently educated as to why what I thought I wanted was a bad idea.  He convinced me.

I agree 100%.  This applies to the diesels too.

Most of this has already been said but just in case someone is paying attention:

1) Better electronics.   Most of my kids toys are more sophisticated and reliable than my trains.  Granted, trains are toys too, but my kids don't have $1000+ toys.  

2) Better QA.   My last 5 purchases were defective out of the box.  I only have 6 locos, so my batting average is pretty much in the toilet.  

3) Better sounds.  This one is aimed primarily at MTH.   My latest PS3 Northern is anemic at best.  It's also inconsistent.  I can barely hear the chatter and the engine sounds at idle (with the volume cranked all the way up), but the whistle could wake the dead.  

4) Better connectors.   There's nothing more frustrating to me than putting an engine on track and hoping that the drawbar is tight.  How much extra do I have to pay for a positive-click interface.  Fifty cents?  A dollar?