Also out of the characters I picked up last time I'm struggling with the below:
- Ares, feel neither as durable as other guardians or powerful enough to be able to deter enemy players. His ultimate is potent if your team can follow up but if not it can also lead to your own very quick death. (Current build: Shoes of the Magi / Sovereignty / Heartward Amulet / Void Stone / Mystical Mail / Mantle of Discord)
- Awilix, finiding it too hard to get into damage range without being put to low health and her ultimate attack just requires too much set up to be used effectively without offering much extra compared to other character ultimates which are much easier to use. (Current build: Warrior Tabi / Jotunn's Wrath / Hydra's Lament / Shifter's Shield / Titan's Bane / Deathbringer)
- Fenrir, to a much lesser extent than the other two. Just feel like I'm a bit useless outside of when I use my abilities as I'm finding it hard to make a difference with basic attacks. Wonder if this is normal for Fenrir or should change to a more attack speed + Hastened Fatalis build? (Current build: Warrior Tabi / Jotunn's Wrath / Breastplate of Valor / Shifter's Shield / Bulwark of Hope / Titan's Bane)
Ares - Keep in mind his passive is that building aura items gives you 10 power per aura item. You are building aura items so you're obviously aware but because of this extra power for building tanky you don't really need shoes of the magi, get the cd boots.
Also his 2 makes him (and teammates) very tanky. Rank it p early, either 1st or 2nd along with his 1. The little bit of cd that boots will give you mean more of these so you're harder to take down.
If you feel like you're being killed quickly while your ult is going off use your 2 before you ult. It will give you those extra protections to survive any burst. You can even use your 2 without causing blink to go on cd.
Awilix - On Awilix I personally build boots, jotunns, BoV, bulwark, titans, situational item. This will give her a bit more tank to survive due to the health and the shield that bulwark can provide. Also you will get max cd so you can setup your ult more often.
If someone on your team picks a god with knockup (Bacchus, Jing Wei, Sobek, geb etc) then it is a good time to pick Awilix as you won't even need to setup your own ults.
Also if the enemy has someone with a jump you need to be the bane of their existence. If your ult is up keep a close eye on them. You can stay in relative safety and just wait to pull them out of position rather than go out of position yourself.
Fenrir - Your build is fine, you might consider getting hide of the urchin over shifters shield but that's personal choice.
However what you're feeling is expected with that build. You're going the bruiser build, very good early, you will be rolling the damage/kills. Mid to late game you transition to more of a frontliner for your team. using the stun on your 1 and the ult to setup for your dmg dealers. While not quite as a good frontliner as a bruiser warrior it works very well.
You're going to need a different build if you want to do auto attack dmg.
Boots into some lifesteal. Devos is great if you can get the stacks, asi if not. Then executioners into some crit, best probably being deathbringer and wind demon.
The final item would be situational, some defense wouldn't hurt, frostbound to help stick to the target, fatalis would be fine or even a titans bane if the enemy team is really tanky.