Top line is fine and is basically all I use. That will enable you to make some overall generalisations on player type which is all we need the HUD for in MTT"s. We will never have a sample size big enough to mean much and stats will sku anyway as blinds increase.
Saying that, I couldn"t play MTT"s in any volume without the HUD. Easy to spot the fish, the LAG"s, the TAG"s etc etc. I am probably a little over reliant on it on occasion. Note taking is important for the post flop stuff, whether villains play draws aggressively, their deep 3bet call range as examples. Whenever we get to showdown and see villains hands, I am trying to draw conclusions on playing style. Obviously this all becomes more difficult the more tables you add.