Amritraj´s advantage, which isn´t fair to new tennis fans as TMF,FedRulz,APMERK,NathanielWear and so on, is that he has watched- and played- against both players or watched closely both.Me and some other posters here have done it, too, and I will expose, segment by segment, why Laver would beat Federer in a direct comparative:
Serve: Fed´s a bit better, and both had a pretty good second.Ad Federer
Overhead: both verys trong and few mistakes, so it´s even
Volley: not even a match.Advantage Laver
FH: Fed´s a bit better, which is saying a lot cause Rod´s one was a top one
BH: Fed´s one is good and versatile but not in the same league as one of the best ever backhands, able to compete with any other backhand when hit top spin, flat or sliced.
Lobs and Drops: it wouldn´t be fair to compare, since Fed´s never faced a net player, thus never practised lob in the way Laver ( and old pros) did.So it won´t enter the contest.
Tactics:Laver was the Master of tactrics and unexpected.Federer has never played at that level
Moves: Both great movers, bit advantage to Laver, the rocket
Fitness: both verys trong and fit.I would put them at the same level
Menthal toughness: Laver wouldn´t let anybody own him in the way Fed´s been owned by Nadal.Just because of that, Laver wins by a very clear margin
So, Fed wins in serving and forehand and Laver in volleying, backhand, tactics and menthal strength.
Laver wins it all.