Marking stuff is a valid strategy! :D You can use your mouse, you can notice that some spikes are set in similar positions and you can actually use the mechanic to show the spikes that help you most. When play-testing I wanted to be quick about it, so I used my fingers. ;p But yeah, making this into a bigger game without any changes would probably get quite tedious quite quickly, you're right! Would need some more cool features for something bigger. ;)