Gremlin is an armor that probably everyone should have. It's very adaptable, it has very good durability for it's level and is quite affordable. You can add a set of Mark.3B plates and hunt robots with it, you can add 6B plates and go hunt Allophyls, or just add the 5B plates and hunt a wide variety of low level mobs all over the universe. It's one of the most useful armor sets in the game. The Avatar bound Viceroy armor on Arkadia is essentially the Gremlin armor but with a different skin.
Jarhead seems to have gained in popularity since Loot 2.0 came out and people realized that armor decay is compensated for in the loot (Jarhead has a very nice distribution of damage protection but has low durability, like Ghost).
Or you could go the Bear route like I did long ago. Bear would definitely be an upgrade from your current Shogun and it has a nice distribution of damage protection, everything but shrapnel and electric, which can easily be added with armor plates if you ever need that. Bear also has very nice durability (2950 like Gremlin). Only thing is Bear will probably become too small for you more quickly than Jarhead would. Jarhead is also still cheaper then Bear at this time, which doesn't really make sense to me since loot 2.0 and especially when you consider that the blueprints for it haven't dropped in a couple of years now either. It's only a matter of time before Jarhead catches up with the Bear price.
If you like to mainly hunt robots, you could get yourself a set of Mah'ketta which is great for those. It doesn't have Shrapnel protection but the Burn/Pen stats are essentially the same as Adjusted Nemesis for about 1/3 of the cost. However the armor looks a bit odd, especially the Helmet.
Another option of course, if you often like to hunt robots, would be to get yourself an Adjusted Vigilante armor. It's less versatile than Jarhead or Bear but it's a very nice set with a 20% increase Dodge chance buff (like Evade but for long range damage types: Burn/Pen/Shrap). It's more geared toward hunting bots though, so you might find that it's not so practical for hunting animals or mobs that deal close range damage (Impact/Cut/Stab).
So to sum up, here's my recommendations, ranked from most strongly recommended at the top:
1. Gremlin
2. Jarhead or Ghost (Ghost is cheaper but Jarhead is better)
3. Bear
4. Adj. Vigilante
5. Mah'ketta
Cheers o/
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