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.
It seems to me that FIFA and UEFA are experimenting too much lately with all competitions and that their main motivation is to increase earnings and not to increase the quality of the competition.
When you include more national teams or clubs in the competition, the quality of the competition decreases, but the earnings increase due to more matches.
However, this means that key players in the main teams in the Champions League will have to play a lot more games, will be more tired and there will be more injuries.
I believe that the coaches and players of the main clubs in the Champions League are not happy with the proposed changes to the competition, but no one asks them for their opinion, what is shame.
Klopp and Pep already complained last year about the fact that their main players have to play too many games in the season, but nobody listens to them and now there will be even more games per season.