Well now, I'm not an expert on YGO or anything and as soon as one of the real knowers come around they'll probably point out the flaws here but if you're planning to go fishing for the Ys and Zs and whatnot then you are missing the easiest way to do it: Shining Angel. Unless I'm mistaken, the ability to fish out any Light monster with an Atk of 1500 or below practically means that you get to search for any part of the set except X-head Cannon and not only that, but you also get it straight onto your field where you need it to be. To further improve on your searching capability, you should also throw in a copy of Graceful Charity if you've got one. That card fits snuggly into basically any deck. ^-^ You've also got too many traps here. With one fourth of your deck consisting of them you're liable to run into a lot of dead draw situations with it if your opponent gets Jinzo or Royal Decree out on the field. Cyber summon blaster is just plain redundant. That 300 extra damage is hardly useful if your strategy is to plunk down the big fusion monsters on the field. Similarly, I can't find any justification for dragging in the Shooting Star Bow here seeing as how XYZ & co can clear out pretty much anything you want from the field. Seeing as how all of the XYZ and WV fusions (Except for XYZWV itself) have effect that rely on discarding, it's kind of counter-productive to carry around a card that leaves you with less (if different) cards in your hand than what you started out with, so Magical Mallet looks kind of like a waste here.
Also, Trap Jammer and Magic Jammer are kind of meh. Again, many of the fusions can handle face-downs before you trigger them, and the discard of the Magic Jammer hurts a bit. I think Magic Drain would be a better option there. I'm also going to suggest dropping one each of Z-metal Tank and Y-dragon Head. As it is, you've got so many of those small union monsters in your deck that you're liable to end up with a seriously cluttered starting hand. You should have enough searching and graveyard retrieval to fetch them without maxing out, really. Compulsory Evacuation Device also strikes me as a bit of a random choice in cards, something to actually keep your union monsters out of harm's way before you fuse them like Negate Attack or Treathening Roar might be better suited for that slot (As you can hardly expect to always draw into Frontline Base every time). Also, My Body as a Shield seems a wee bit expensive for a deck already running Solemn Wishes and Return From the Different Dimension with only Solemn Wishes for healing. I'd suggest dropping it, since it's quite liable to end up as a dead draw.
Now to patch up that gaping hole it would leave, I'd like to start by suggesting a full three copies of Shining Angel. Like I said, there really aren't many cards that can sort out the fetching of those parts better. Also, most of the creatures in this deck have an Atk below 1600, which means that Hydrogeddon can really lunge at your throat before you even yet started, especially since Swords of Revealing Light pretty much constitutes the whole of your attack blocking potential. To prevent that, it might not be a bad idea to throw in another Cyber Dragon for field control purposes. Since you're going to fuse most of your monsters anyway, I'd also suggest throwing in a copy of Limiter Removal to exploit for a three or four monster rush (Or five if you played return) at a suitable moment. It's also good if you're facing a strong monster and haven't drawn into anything useful to counter it with. Now to make up for the spell and trap countering cards I removed, I think two copies of Cyber Phoenix should do quite nicely, as their special ability should help to keep pesky little cards like Enemy Controller, Sakuretsu Armor and Snatch Steal away from your big monsters. They also have enough Defense to block any Hydrogeddons from overruning you, if need be. Finally, a bit of extra drawing ability never hurts, so I'd say that Morphing Jar and Pot of Avarice (If you can get them) would be very nice cards to add, although extra copies of Return From the Different Dimension, Frontline Base, or Roll Up! can all be used as substitutes. Book of Moon is also nice, both to exploit your flip monsters and to counter stuff like Cyber Dragon or the monarchs.
So basically, I'd suggest...
-1 Magical Mallet
-1 Shooting Star Bow - Ceal
-1 Trap Jammer-1 Magic Jammer
-1 Cyber Summon Blaster
-1 Compulsory Evacuation Device
-1 Mask of Darkness
-1 My Body as a Shield
-1 Y-Dragon Head
-1 Z-Metal Tank
-1 W-Wing Catapult
+ 3 Shining Angel
+ 1 Graceful Charity
+ 1 Limiter Removal
+ 1 Book of Moon
+ 1 Cyber Dragon
+ 2 Cyber Phoenix
+ 1 Morphing Jar/Frontline Base
+ 1 Pot of Avarice/Return From the Different Dimension/Roll Up!
Well, hope that helped, and hope that some of the more well-versed forumites will come around and do a better job. ^^ Also, make sure to add in any of XY, XZ, ZY & co if you get your hands on them, as you can't always expect to get all three of the XYZs out in one go. It's not like taking them along hurts, anyway, since they're all in your fusion deck.
