I think it is still early to bet on Champions League matches from this round. I'm speaking for myself at least because there are still so many teams that I don't have any idea about. I tried to bet on such teams in the past and it didn't end up well for me. 
It feels safer to bet on the matches of more known teams than these for me.
This is the last season with the current Champions League format indeed. I wish it didn't change because I find the new one ridiculous. You are in a league-like system but you don't even play with all the teams there. I don't know how fair this system is going to be but let's see. If it doesn't work out well they would return to the previous version I guess.
It feels safer to bet on the matches of more known teams than these for me.This is the last season with the current Champions League format indeed. I wish it didn't change because I find the new one ridiculous. You are in a league-like system but you don't even play with all the teams there. I don't know how fair this system is going to be but let's see. If it doesn't work out well they would return to the previous version I guess.
bet only on teams that you know their strengths. and you can predict your victory better. don't waste money on bets that are hard to guess.
regarding the new system in this competition, it increases the number of clubs that will be participating and with the League format, maybe it will be more attractive for every club. but we haven't seen which one will be more efficient we can see how it will be successfully implemented and successful or will leave controversy at the end of the season.