Bernard is a very exciting player for a club to sign, but not really the right player for Liverpool to go for, Arsenal would be a much better bet. Most analysis of him I've seen suggests he's not really ready to move up to the premiership, it sounds like matching the contribution of someone like Oscar, or even Sterling, would be a good first season for him. Arsenal are already in the top four and so can afford to let him grow in the team but Liverpool can't really.
The likes of Eriksen and Ben Arfa are much better known and therefore much less exciting, but I think everyone would agree that they are more developed than Bernard and can make an immediate impact. You never know with young players, Bernard could come in and start playing well straight away, but it is a big risk.