You can double tap and drag to immediately to start a selection with your finger. So if I wanted to select [this sentence] I would double tap on [this] and keep

You can double tap and drag to immediately to start a selection with your finger. So if I wanted to select [this sentence] I would double tap on [this] and keep my finger down on the second tap, then drag over [sentence]. You can keep dragging to select a whole block. I haven't seen this feature mentioned anywhere but I just discovered it one day for the same reason you are annoyed. The feature works on iPhones and iPads alike.