Considering adding this to my train system. Good idea or bad?

[warped hearth]

I've noticed that my trains that collect ore take a long time to get from my newer, far-out mines to my smelters in my factory. These standard trains only have 4 cars, so they don't really have enough capacity to utilize the full throughput of every mine.

To solve this issue I'm considering setting up a system where the short 4 car trains pick up ore from far-out locations, but instead of driving all the way back to the factory, they go to the closest bulk transport station, where a consistently-scheduled really long train picks up a crud ton of ore at once and delivers it all to another bulk dropoff hub inside the main factory, where the ore gets handed back to shorter trains for final delivery.

Is this a good idea? Are there any glaring problems with this plan?

[humble hornet]

you'd need an extremely long distance to really make it worth the effort

if you're not able to use the full output of a mine due to loading speed, you can add more stations in parallel

if you're not getting enough trains to pick up ore, you'll need higher station limits
or more stations in parallel, i treat the two limit=1 stations as an overall limit=2 station

[ripe quest]

Ore backing up on the outposts is not a problem by itself. In fact, if all mines are running 100% of the time, it means you're not mining enough ore and need more outposts.

Do your smelters get enough ore?
If so, good. No need to change anything.
If not, that can have two reasons: Not mining enough ore or lack of transport capacity.

From your question, it looks like transport capacity might be an issue. phflack gave you some pointers on what to do to in that case.
We would need more info (screenshots!) to be sure though. (or give more specific advice)

[warped hearth]

Yep y'all are right, the better solution is to have more stations in parallel for each mine

I realized that something that would complicate the big train system is I would have to add something that prevents trains from potentially taking cargo from the bog train's dropoff depot all the way back to it's pickup depot

[ripe quest]

That could simply be done by using three different sets of schedules and station names (pre ore type).