A couple of things. I'm assuming that you're playing Expanded, since a few of the cards on that list (such as Virbank and Octillery) have already rotated from Standard. If that's the case, you should consider the following:
>There's pretty much no reason to not take 4 VS Seekers. They allow you to recycle ay supporter in your discard pile so they are very powerful. This means that you usually run only 1 or 2 copies of each supporter, saving you some space. If anything is absolutely critical for your deck you run at least 2 to significantly decrease the chance of it being prized. Usually, the only one I run 3+ of is my main draw supporter (Sycamore in Expanded. Cynthia gets the job done in Standard too). With supporters like Lysandre/Guzma and N I usually only run 1 or 2 of each (definetely 2 Guzmas in Standard because of the lack of VS Seekers, but you can get away with just 1 in Expanded).
>Discarding is really not that terrible in this game, so using Sycamore as your main draw supporter (discard hand, draw 7 cards) is pretty good. Using 3 or 4 is good imo. 2 is fine depending on the deck. I think You should replace the Shaunas with Sycamores. If you still want to use Shauna, just replace them with Cynthia (it does the same thing, but you draw 6 cards instead of 5). You can combine this with 1-2 N cards to add disruption (N'ing your opponent to 1 card can be devastating and clutch you a win in a losing game).
>If you're only attacking with Honchkrow and Latios, the most important energies are the DCEs. Your basic energies are just a backup, so I don't think you need very many of them. In fact, you could get away with using only 4 DCE and nothing else. That said, you absolutely must take Special Charge to recover them. I used to run 1 Special Charge in my Night March deck, but now I have to take 2 because Puzzle of Time is banned (rip). If you can burn through your deck quickly you shouldn't have a hard time drawing the DCEs. Having 1 of them prized is fine, 2 is kind of bad but it has a very small chance of happening. The chance that you prize 3 or 4 is practically null, so I wouldn't worry about that.
>If you want to take Virbank, I think you should cut down on the poison barbs and use Hypnotoxic Lasers instead (they are still kinda expensive though, so maybe not).
>If you want to focus on Honchkrow's attack as your main strategy, I think I'd be better if you cut the extra fluff (Latios and Seviper. Giratina is fine if you have a way of discarding it more than once. Octillery is OK, but Shaymin EX would be better if you can afford it) and added instead a line of bats (zubat, golbat and crobat). Golbat and Crobat place damage counters upon evolving, and you can de-evolve them to recycle the effect with either Devolucion Spray, or recovering the 3 cards using AZ and Super Scoop-Ups. You'll spread damage faster that way than using poison.
>You won't need heavy discard like Night March, but running 2 or so Battle Compressors seems like a good idea regardless. You can discard your Giratina, you can discard supporters so that you can access them via VS Seekers, and you can discard any cards that won't be useful anymore in any particular game.
>If you follow my suggestion and take somewhere between 4 and 8 energies (4 being just the 4 DCEs and 8 being what you're currently using), energy lotto is not that great. You'd be better off running Trainer's Mail since decks (save for some exceptions) tend to have a higher proportion of Trainer cards over anything else.
>I think Field Blower is fine at 2, specially if you're taking Stadium cards since you aready have a different way of discarding your opponent's stadium.
>Since you are taking a non-EX/GX deck, you would really benefit from Shrine of Punishment. That's a lof of damage counters you would be placing. Mostly to decks that rely on EX/GX, but stuff like Shaymins and Tapu Leles still take damage in between turns. The other good option (which might not be ideal since you also take damage) would be Team Magma's Secret Base. If your opponent has a full bench, they're taking at least 130 from your Honchkrow (2 damage counters each pokemon + 10 base damage).
>Underground Expedition isn't bad, but you're better off discarding your hand and drawing 7 cards straight up (Sycamore).