Thank you for those ideas, I will begin research for making a lightning node/electrum server (I remember searching for Lnnode 2 years ago but it was a little complicated for me and I didn't finish it)
It would be ideal if you try to find a specific purpose in everything, why you are doing it, not only because you want to make a contribution. Your contribution will be much more useful if you do something that will work even without your daily physical engagement.
Over time, different problems always appear, direct or indirect. It is a greater contribution to solve such things than. I would say that the number of nodes is not the weakest point of the Bitcoin ecosystem.
I totally agree with you. I was thinking to help small shops in my town to accept bitcoin and help them install a solution but I found that they were not interested sadly (I asked like 20 or 30 people in the center of my town but they took me for an alien or something ^^)
So yeah I know I want to do things with Bitcoin because I am hooked but I don't really know what to do. Running a node was easy and I love working with hardware so that was my first choice while thinking I was usefull for the network.