As a fairly new Ariadna player myself, I've learned a few things about the faction that have been successful for me:
1) Cheap orders are your friends. Ariadna has a lot of great powerhouse models that you will want to dump orders into, but you need the orders to do it! 3 Line Kazaks (one of which is my Lt.) is the beginning of each of my lists.
2) Camo is one of our strengths, play to it. I'm not saying you need to spam camo (though I do), but just that having a few models with camo can be very powerful. I have managed to land many kills with combat camo attacks from my tank hunters,
SAS, Uxia, antipodes, chasseurs, etc. Crippling your opponent's order pool in a first turn alpha strike is almost guaranteeing a win.
3) This is more of a general tip for list building, but make sure every model has a role while also having some redundancy in your list. For example I take two tank hunters (one autocannon, one
AP HMG) so I have options for long range weaponry. I take a chasseur, Uxia and a
SAS to give me three infiltrators who can be where I need them to either complete objectives or prevent my opponent from completing his. I take antipodes for mobility and sensor, etc.
As to your list specifically:
1) Love veteran kazaks. The T2 rifle option with the x-visor is brutal at all ranges and can get just about any job done. He can engage at medium to long range or get up close with the flamethrower. Having sixth sense level 2 is also pretty nifty, as Ariadna ironically has few ways to deal with stealth. If need be, he is a good option to go in and force a camo marker to react or be discovered. For a heavy infantry the vet has great speed with 4-4 movement, making him faster than some medium infantry! I've never run 2, or the
HMG option.
IMO a tank hunter is a better buy simply for the combat camo attacks, but a bs13
HMG that is decently fast and tough to kill is nothing to scoff at. My vet kazak with the T2 rifle is another staple of my lists, really can't go wrong with any of the loadouts though.
2) I would personally run the
AP sniper rifle over the ojotnik if you have the points/
SWC. The ojotnik has a bit higher damage, but the sniper rifle gives you a range band bonus. Either way you get an infiltrator with mines which is an awesome combo. You could also proxy this guy as the foxtrot sniper with the same loadout for 9 points cheaper! Those 9 points are a line kazak (read one more order).
3) Haven't tried moblots myself, but they seem solid enough. Paramedic is a pretty good choice for Ariadna because we tend to have a lot of models with higher than normal physicality. Using doctors and paramedics can be a bit tricky as they're usually in a spot to get shot at if they're trying to patch a buddy up. I've gotten the best use out of my doctor by having him hunker down prone behind my big guns and healing when needed. Looking more closely at moblots, I like the panzerfaust option as well as the
MSV option.
These are just my thoughts based on the games I've played. Like you, I was drawn to the beautiful model that is the veteran kazak. Best of luck to you and welcome to Ariadna, the only real men in Infinity
P.S. if your Haqqislam player runs a Lasiq with a viral sniper rifle KILL
IT TURN ONE. That thing will mince your veteran kazaks. If your opponent is smart, he will hold it in reserve and deploy it in a way to start shooting turn one. Do whatever it takes to eliminate it turn one and you will be able to breathe a lot easier and also gain the advantage at long range.