For small objects like fences, chairs, pots, etc… I think destruction is fine. They are small enough that players can destroy and not notice a big difference or drive through a fence and keep going.
As for huge objects like buildings, HESCO blocks, etc… I disagree with them being dynamically destructible. Reasoning being is that its invulnerability to destruction willl allow the players to tell which buildings/objects are put in the map or player-made. The invulnerability to destruction should also be an obstacle for players to work around, rather than just detonating explosives or shooting it to get through.
Looting would be a nightmare for people without gear, because if a town is fully destroyed, assuming destruction affects the loot, there will be little to none the player can find. This is a huge bottleneck for players who just spawned, and until someone fixes the building or it resets, it is not going to be a fun time.
Fixed openings such as windows and doors are also places for players to look out for when they suspect someone camping in a building. Dynamic destruction only adds more holes that players have to worry about, as good as this sounds in paper (and executed in R6S), I think players should look out for building camping players around doors, window, corners, and walls in this survival game - where players naturally suspect other players to be. I think this gives more emphasis to survival because of intuition and map knowledge, rather than “I died because he made a hole in a wall that wasn’t there before”.
As for particles, I think 3.0 particles are fine, however I do not mind remaking it and improving the particles. Either way is good.
EDIT
Having a destruction entity that players can use in map making would be nice though.