I think you'll want a bit more on the low end of your mana curve. I suggest Fatal Push instead of Oblivion Strike-- maybe 3x Fatal Push and leave one of the Oblivion Strike. Anguished Unmaking might be good for the sideboard to deal with the Saheeli Rai + Felidar Guardian combo-- probably in place of the creatures you have in the sideboard.

Ayli, Eternal Pilgrim adds a deathtouch element, and Drana, Liberator of Malakir provides first strike (both with Odric, Lunarch Marshal are amazing). Maybe 2x Ayli, Eternal Pilgrim in place of 2x Cliffhaven Vampire. You're very heavy on 4 mana spells, so reducing that and getting more into the 1 and 2 mana range will be useful.

2x Aetherflux Reservoir seems to be a logical inclusion.

Good luck! Looks like a fun deck to play!

For your land I would replace Forsaken Sanctuary with Concealed Courtyard

Just a few notes:

I recognize you are trying to keep this super budget, but I feel like if you even get just a couple Concealed Courtyards that'd make the deck a bit faster (instead of having to play a dual land tapped on turns 1, 2, or 3, you could immediately use it).

Murder is only like 25 cents, is 3 CMC and an instant vs. Oblivion Strike which is 4 CMC and a sorcery. I feel like those could be switched out.

Then in the sideboard, you have 6 cards devoted to artifact destruction, that may be a bit much. There's a lot of vehicle-based decks out there, but you can use creature and artifact destruction to deal with them.

I think this is a good deck though, nice bit of aggression and resilience with lifegain and such.

Also, for lands, Shambling Vent is a solid addition because board wipe cards are starting to creep into the increasingly aggro game of Standard (e.g., Yahenni's Expertise, Biting Rain, Flaying Tendrils, etc...). Having a manland can swing a game for you, particularly one with lifelink!

Anguished Unmaking Just seems way better than Oblivion Strike. Costs one CMC less, can be cast at instant speed and the 3 life lost isn't that big of a deal with the massive amount of lifelink in the deck. Murder is a cheaper alternative, and I agree with previous comments that Ayli, Eternal Pilgrim and Concealed Courtyard are both worthwhile inclusions provided you have the budget.

I like the deck. What are you doing with all the life gain? Treat it as another resource and use a creature like Glint-Sleeve Siphoner for card draw.

I also like Fatal Push if you drop in some Evolving Wilds. Even though this is a budget build, that would be a nice combo.

BioProfDude thanks for the recommendations. I like Fatal Push and have been considering it but wasn't ready to pay for it. Thanks! Shambling Vent is also a good recommendation.

Hamster2558 I totally agree. Thanks!

Thanks everyone else for the suggestions. I will look at them.

The one thing I would be worried about with this deck is the mana curve. You are really heavy on the 4 drops, and with how light you are on removal (7 out of 60) any true aggro deck will run you over before you can get established. Authority helps this a lot, but it only buys you a turn or two. I would lighten up on the creatures a bit and go with more removal. Others have given you some great recommendations so I won't bother.

Now I understand budget, I'm in the same boat, so here is how I would prioritize.

1) Good cheap removal like Murder. Your LGS will have tons of copies and a playset will cost you about a buck. 2) Mana Base. They're a little pricey but they will make a HUGE difference. I would prioritize Concealed Courtyard over Shambling Vent, though both are great cards. 3) Sideboard tweaks. They key is to think about specific matchups. What would work against the main archetypes? How do you stop vehicles? Or Copycat? Or GB Snake/Counters? Go from there.

I made a similar but much more controlling deck, and it shows up in the Similar Decks list at the bottom of yours. Check it out for some ideas.