So hope you don't mind but I took a quick look at your loadout and I think I can already see why you're having trouble against them. If the duke + smg one is what you're using in pvp, then sorry, but against those weapons you're gonna definitely have a bad time. The duke is a monster from medium-long range, but it doesn't kill fast enough to deal with a titan or hunter who's rushing you at close range, not to mention how unforgiving it is if you miss even a single shot. I see a few people using kinetic smgs in the crucible but they're generally few and far between because right now they're mostly just not very good, esp. the energy ones. As someone who also struggled to deal with heavy users of them, I think I can make some recommendations of weapons/armor you can use to help you. For weapons, you can try the chaperone to outrange them, Cerberus+1 to shred them before they get too close, or a high impact fusion rifle with backup plan. You can also just try using a god-roll shotgun yourself, like the one shaxx is selling. For armor, you can try using antaeus wards to reflect their shots back at them, mk. 44 stand asides to tank the shot with an overshield, or synthoceps paired with bottom treee striker (makes your melee range ridiculous, all you need to do is land 1 headshot with the duke and then you can snipe them with your melee). If you play warlock, contraverse holds + handheld supernova basically shits on them because you can just block the shot and then vaporize them.