-> There is also 1 especial point that I am confuse yet: Some people say they faced problems trying to recover the coins from a really old electrum wallet... why is that? what do I have to do for not having this problem in 10 years from now?
I hope I understood your question. It depends on what Electrum wallet uses to create seed phrase. In the past it supported BIP32 but after version 2.0, it changes to Electrum Seed Version System.