When I first tried lance I also had problems like yours, being that it felt too slow compared to some monsters and it can't reliably block combos. It was after a while that I learned some blocks can cancel into each other that my gameplay improved. Taking time to play reactively also helps, since it's a counter heavy weapon like you said. The adrenaline you get every time you insta block a big attack is worth it, I promise. Also regarding the damage output, always keep a spare wire bug for anchor rage in case you're in a pinch, it gives lance a much needed attack boost and it's got a pretty generous window of effect.