Ideally, you want a pace bowler to keep it around 7-7.5 rpo. Thushara has done this because he bowls to his field. You don't mind a bowler going for 8-9 rpo if he takes 2 or 3 wickets in every game and maintains a low average. Econ 10+ and avg 20+ combo throughout a tournament is pretty bad. It means you are conceding way too many in a game of small margins.
Taking a wicket doesn't always slow down the run rate in T20 (happens more in ODI) because of the nature of the format caused by the limited number of deliveries available. Even after Avishka got out, Pradeep's next over went for 16 - a case in point. He bowls too many short deliveries even when he keeps getting punished. This happened last year as well. Malik or some overseas guy kept pulling him for easy boundaries.
Thushara bowls to a plan and adapts when he bowls to different batters. For example, the way he bowled to Thisara today. That's good to see.
Taking a wicket doesn't always slow down the run rate in T20 (happens more in ODI) because of the nature of the format caused by the limited number of deliveries available. Even after Avishka got out, Pradeep's next over went for 16 - a case in point. He bowls too many short deliveries even when he keeps getting punished. This happened last year as well. Malik or some overseas guy kept pulling him for easy boundaries.
Thushara bowls to a plan and adapts when he bowls to different batters. For example, the way he bowled to Thisara today. That's good to see.