I also have a question regrading segwit. Although I keep my "old" wallet with non segwit address, I've also created a new one that has native segwit addresses (the bech32 P2WPKH type, so addresses starting with bc1). I was aware that I would probably not be able to send or receive from non segwit addresses, but I decided to go for this option anyway, since I heard they are more efficient, so I preferred them over the "transitional" P2SH addresses.

My question is, will I be able to send/receive coins between my bech32 P2WPKH, and the P2SH addresses?

The thing is that segwit adoption is taking a lot of time, so I'm afraid that the "transitional" P2SH addresses get more "popular", and it will take a while for me to be able to really use my bech32 P2WPKH addresses.