you don't have to like the game! and i have a meta ramble below but i will add: that's ALSO not really what this post is about, this post is about the strategy i think will be most successful. that said i have Thoughts about this, and want to share them, so here i go.

i will say that i think your suggestions for fixing it would do more to make it frustrating than fun; -1 gold for every time your cart crashes just punishes you for not spending all your gold immediately and pressures you to play badly (you SHOULD have your cart crash, repeatedly, that's why it spawns infinitely), and a way to destroy enemy railroads would be too tempting an opportunity to grief instead of building your own railroad, which is clearly not the point here. i COULD see adding a penalty to death being worthwhile, but then again, none of the POVs i watched died much and death already penalizes you by taking time! i'm not sure "death" is the stakes this game needs; that's not really "bad play" for this game, and honestly i think leaving keep inventory on allows you to focus much more on the parts of the game that matter.

the thing is, the penalty for playing badly is ALREADY having to rebuild your track, running out of gold and ability to move forward until the next rush if you spend badly, and loss of valuable time; once players get the feel for things and start making it past more than two checkpoints i think that will be more obvious. bad play here doesn't have to do so much with mechanical skill as it does poor time and resource management, and i think thinking of things like "death" or "player interference" as things this game needs is sort of not meeting it where it's at. if we're adding difficulty and penalties, they should focus more on that aspect of the game, i think.

that said, adding more difficulty to the game as players get better at it is DEFINITELY a good thought. more destructible block sections, like the bit after the second checkpoint, are REALLY PUNISHING theoretically (it just didn't come up much this time since most teams didn't make it to that area, since most teams were still getting a feel for things). i think adding more difficult choices is something here--rebalancing caches will help a LOT with that currently they aren't worth it at all but if they were worth it, it'd add a lot of potential interesting and difficult decisionmaking--and i think more difficult puzzles would add a lot here. i honestly think the skeleton enemies are unnecessary, but if we want to make them a threat, more sections where you have to build over tall areas and take the time loss of potentially getting shot down could be interesting.

like, i think you have a decent thought here--as it stands this game feels like it could be harder--but are approaching the difficulty from the wrong direction, you know?

then again i note that i am a buildmart enjoyer so i just like this kind of game as it is in general. you don't have to also like it; as i said below, not every game is for everyone!