I believe this has been suggested before, but I would like to second the need for some buffer block that the trains don't break easily.

Current, even a hand cart will go right through any block in the game including bedrock which seems a little ludicrous.

Updiating on the suggestion. Apparently this user made an addon which adds buffers. So... now we actually have a buffer quivalent until IR devs make their own one. https://www.curseforge.com/minecraft/mc-mods/signal-stuff

Enjoy!