YES.
They're 100% mandatory and especially the Economic Update DLC which features you can assess for yourself here:
Source: http://www.youtube.com/watch?v=iz9JdUfmQO4
Here's a quick review of the Decor Pack 2 DLC
Source: https://www.youtube.com/watch?v=rZIfs4Xyjck
Here's the Style Pack
Source: http://www.youtube.com/watch?v=ghvcLsG3cHE
Also don't forget to check out the rapidly growing number of ship mods and other QoL player based content for free (like eat/sleep/drink HuDs for light survival etc) on Steam Workshop. While you're at it, grab the amazing Asp X that was so well designed below. I LOVE the ability to finally experience a complete walkthrough my ship's interior. Be able to sit, lie down/sleep, eat and use the space restroom while flying it
Virtual tour:
Source: http://www.youtube.com/watch?v=wT09l_P9ecw
Asp X hangar blueprint at Steam Workshop. Note you'll need several specific modules when you go about constructing it.
steamcommunity.com
And if you're into a light Survival/realism game play, check out this mod
steamcommunity.com
Finally, if you happen to be a casual or hardcore fan boy of ED's nemesis aka that-other-game-that-will-not-be-mentioned-here: then know you would be bat sh*te crazy to complain about the ridiculous "cost" of these DLCs in support of the Keen dev.
Especially if purchased on Steam at discounts as high as 50% off. Which is what I bought all 4 of the prior DLC at Christmas last year.
But seriously, don't wait to install the Economy update pack. This DLC is an
absolute must have since it adds the long fan base requested player economy (and NPC to player) economies if you want to play solo and/or trade/interact with NPCs on public servers. And a couple of extremely important game play features/mechanics as well.