My gear is all over the place, I've not really put any thought into it and just swapped out for the highest I can get each time. I've put a few hours into the game this weekend again, but I just can't grind at it and find myself thinking "why am i playing this". Are there any plans to release the DLC's for free down the line? £12 seems a little steep for what I am betting not a lot of content.
you have just defined the single biggest problem with the current version of this game - solo play, and the fact you need the gear in order to do content, to get better gear!
Based on your current build, I would honestly wait till Tuesday and work on it then. Everything will be much more attainable, and harder content is now more realistic for solo play due to new scaling, AI characteristics and world tier system
Off the bat though - I can see you are missing armour on chest and holster which would help with toughness and that is a defining build style in 1.4 - armour armour armour to the point you are roughly 50-55% on armour mitigation(for PVE, not PVP as that will require more)
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To help with 1.4 though the below would be the sort of build stats you would aim for (in terms of FA/Stam/Elec) for a balanced build that also helps with solo play: (don't compare these screenies to 1.3 though)
3,2,1 setup:
4,2 setup
So on both of these builds there is a trend. Around 4k FA, 5.5k stam and 2k electronics.
Armour is rolled on chest, knees, backpack and holster. Gear mods have armour on them as well.
These two builds pulled me through the DZ at all levels, CM missions, CM UG, and the hardest weekly HVT - Solo!
If I was in a group - I wouldn't utilise Nomad as HoK isn't as necessary but I was able to do all the above without Nomad as well - in the PTS each week including the last.
In addition, get yourself over to discord

We have members who don't use mics and regularly have dudes kicking about willing to group up. Some are coming back, some have been here throughout the games existence:
https://discord.gg/3ntfsm6
LFG or just advice, we are always online lol
Finally, in regards to the DLC - up until now they have gone about it in the wrong way in terms of sticking content onto a broken core experience but now, with the changes the UG is now more fun which was their first DLC. Survival is coming before the end of the year and I believe that it will be a big success considering they are putting this on top of a working, balanced core gameplay experience.
But I agree, in 1.3 I simple didn't do the UG unless I knew I had a group from this forum as even with experienced people, with min maxxed optimised builds - the hardest difficulty can still wreck you in an instant.