Engine and aircraft have a big effect. Pa28-161/Lycoming, C172/Continental? & Lycoming, and C152/Lycoming have given me far less icing than Jodel DR1050/Continental O200. Especially until the engine is hot. (after 10? minutes flying.) The O200 is an ice-maker. I've had the worst ice on warm, cloudy, summer conditions. (Warm for Scotland )