When the new edition came out there was a general call that (in combination with TLOS) the changes to the terrain rules made terrain irrelevant in the game.
I never really subscribed to that theory. It certainly had its impact downgraded relative to what it was in 7th Edition but I still felt that it had an impact on the game. Part of the reason for the general view was that most tables had had 4-6 pieces of terrain on them and those terrain pieces were either hills or woods (sometimes ruins which acted like stone forests). Both had blocked line of sight but woods also slowed movement to half speed and prohibited marching.
What you rarely saw on tables were any other types of terrain e.g. buildings, marshes or ponds etc.
Woods now have some variety to them – if you use the Mysterious Woods’ rules, which we do – so you need to calculate the risk before you enter them. While they don’t limit the extent of movement they do have benefits/downsides if you finish moves in them – both for combat and for shooting.
I play most of my games on a Realm of Battle Gameboard and I love how it works for higher ground and TLOS. I understand that a flat table with hills reduces some of that rule interaction.
While I know some people hate the building rules, I think the introduction of buildings into games has been a large positive. Once the “dirty reform” into buildings was prohibited, most of the problems around buildings evaporated in my view (one rule I would like to see is to allow skirmishers to charge from a building so that you can’t anchor your flank with impunity – or at least burning two enemy movement phases).
(Due to the nature of terrain at the events I run – buildings on base boards – we play that the whole base blocks LoS – that is an abstraction that helps movement. It could just as easily be played the other way – TLOS – but movement would become more "gamey".)
So from my point of view I like the terrain rules (which was a surprise because I hated the removal of area terrain in 40k). I think they can be improved particularly in increasing the penalties for ranked/mounted troops in woods.
However part of my preference for the new terrain rules is the so-called “cinematic” aspect whereby we now see much nicer terrain on the tables – which for me is a key part of my enjoyment.
Rule Change: B-