currently I am trying to build a "realistic" park and themewise I ha ve a nice spot for a mine train. Now I am struggling with building one which has reasonable height (like max. ~30m). But I can't seem to figure out to get a decent lenght on that coaster because I lose speed too fast (and a second chainlift is a no no for me

). How do you build your mine trains? Lenght, average/max speed, which elements do you use? What is typical for a mine train? Dunno if that question makes sense, I am kinda looking for inspiration and youtube is no real help as it has quite some rides but hardly any video describing how the coaster is built.
@BlackShark gave some really good advice. Hopefully I can add a few more things...
The Canyon Runner "mine train" coaster might be on the family tab but it's not required to actually be a family-friendly coaster. It can do down at a 60^ angle so can accelerate very quickly and easily reach speeds of 50+mph. It's thus quite possible to make it lethal, especially because the max bank angle is only 45^, so you don't want to be going into turns too fast. The upshot is, you should have no trouble getting "green" excitement of 7 or above due to speed and its potential for multiple airtime hills, but with that will almost inevitably come "green" or higher fear (4+) unless you're careful to slow down before making turns.
The thing about "green" (4+) fear is that only about 20% of families will ride it if the fear is above 4.0, only about 10% if the fear is above 4.5, and none at all at 5.0 and above. So, how you build the coaster depends on your target demographic. As things stand at present, coasters with excitement of about 5, fear slightly less than 4, and nausea of 1-2, are simply the most popular and profitable rides you can have. Everybody flocks to such rides, and the Canyon Runner can have very high throughput with multiple long trains. But if you go for "all green" stats, you'll only have teens and adults on it, and it won't make nearly as much money, especially if it has to compete with a mondo hybrid or other "big boy" coaster.
Thus, you generally want to build a Canyon Runner for families because you can make better "big boy" coasters on different chassis. And that primarily means keeping fear just barely below 4, which means keeping the speed down to Wendigo levels, which will pull the excitement down to the 5-6 sub-green level. To do this, you can either not have much of a lift hill, so even with a long, steep drop, you still won't go too fast, and the overall track will be relatively short. Or you can go with a tall lift hill but then descend in a long series of short dips and climbs to keep the speed down, instead of a series of big drops and big hills like with a wooden coaster. This results in a relatively long track. However, it's quite possible and also desirable to have the track all tangled up with many head-choppers and switchbacks over itself, and the longer the track, the greater the prestige, so long tracks can be had in a relatively small footprint. And the longer the track, the more trains you can run so the higher the throughput of what, if done family-friendly, will almost certainly be a very popular ride.
As to multiple trains, the real limit is that the Canyon Runner has a long train, so reload time is quite long. If you want to run multiple trains and keep them all as long as possible, you absolutely have to use a station with entrance and exit on opposite sides of the platform. Then you can put the exit gate in the center of the train, which minimizes the time required for the old customers to leave the platform, and put the entrance near the rear of the train, which helps make sure the last cars get filled. Still, for a track of reasonable length (say a 25m lift), you should only try to run 2 trains due to the time required for old passengers to exit.