It really depends where you go and when.
To be honest, one of the last places you ought to be going to see loads of overtaking, is Berwick.
A lot can also depend who the opposition is. Lots of teams turn up at certain tracks and are beaten before the start of heat 1, but, if the opposition are prepared to give it a go, then you can be entertained.
Last weekend, for example, I saw a dreadful meeting at Berwick (Berwick v Newcastle), but saw a half decent to good meeting at Brough Park the following night between the two sides. Last night at Workington I saw another poor meeting, where I saw two overtakes all night. But, I have seen some great matches at Workington (both when Newcastle have been there and also when they haven't).
Somerset is usually good value and Scunthorpe isn't too bad either.
Glasgow, usually, can produce decent racing, now they've adjusted the track.
I've given up on the EL (TV). I've even given up going to Cardiff for the Grand Prix.
I can't comment on the NL. Perhaps a NL fan can respond.