Limping during the first few levels of a tournament is fine in my opinion. The blinds are very small and there's probably no antes yet, so we're really not concerned about stealing the preflop pot just yet. I think its a perfectly valid strategy to play a very wide range of hands early in a tournament - what Daniel Negreanu calls "small ball", you don't have to pay much to see a flop and when you do hit the flop hard, you hand will be very disguised and hard to read properly and you might just be able to win a sizeable pot if our opponent can't find a fold with their AA or KK type of hands. But once the antes kick in and the preflop pots get larger, that's my cue to stop limping in with all the other donks, and to start getting more aggressive against them.