THATS WHAT I FORGOT TO DO
Sorry WMBQ, I tend to do that... Storm would agree with me. .____.
lolno i keed
There are a few issues that need to be discussed however, not that there ever isn't in any team. Firstly, your Ice weakness. Water types often pack Ice as a coverage move, so Rain teams will seriously hamper you. Keeping Roserade alive and rockin' that STAB Giga Drain will give you some semblance of a counter measure, but it's only a matter of time before it falls to the super-effective moves. Particularly if they're boosted by an item/the opposition with said Ice move is a sweeper. Once Roserade is gone, Umbreon (since Moonlight is a waste of time in the rain) will quickly weather down, and your team will instantly fall apart and be taken down by the oncoming tidal wave of watery/frozen death. Hail teams will also **** your shit up with STAB Blizzards, but it's not like they're at all common. Enemy Mamoswine will also be a problem since Umbreon ain't gonna switch in and Curse on those uber-powerful EQs.
Next, as ya mentioned, you ain't at all equipped to handle powerful Fire moves bein' thrown about. Sun teams' Fire types will knock you around pretty hard once Salamence goes down, and boy does an offensive Salamence with a Life Orb go down fast.
Sandstorm teams also hamper Umbreon's effectiveness. While Conkeldurr fears no Rock moves, it's not about to switch into a Terrakion or a Rhyperior. Two Ground immunities and one Rock resist means you'll be at a disadvantage up against stereotypical Sandstorm teams' heavy hitters, and one wrong move won't lose you the game, but might begin a full on collapse of the team if you lose an important Poke.
So yeah, this team has at least a few problems with EVERY type of weather based team. That ain't good. If you've figured ways around it that I don't see, good on ya (... do tell me your secrets if so >_>). If you've been noticeably struggling with weather as I'm predicting, you'll need to fix this issue ASAP to keep your win/lose ratio up high.
Next, this team is very physically inclined. Roserade is a special attacker, sure, but it's uninvested. Salamence is also mixed, which means it's not hitting like a complete monster. It's also more physically defensive inclined with two +Atk +Def sweepers. It's kinda pointless to have two sweepers doing the same duty unless they're designed to help the other Poke sweep by weakening counters, and I don't think Umbreon and Conkeldurr share to many (correct my if I'm wrong, 'course).
Speaking of Conkeldurr, it's not specially bulky. +SpD nature and 252 EVs later, it still isn't bulky. You can't rely on it to tank special attackers, even if they're unboosted. Those EVs let it survive assaults and smash back with a Drain Punch to heal itself and KO unless it's say, a Reuniclus. I can see why you therefore have Umbreon and Roserade on your team, but the latter isn't supremely bulky, while the former can't tank enough under weather conditions.
Point being, this physical inclination is also a slight problem. Definitely not as major as the team's weakness to weather, but if ya want to optimize the team to be as best as it can be, a problem that you may want to tackle. My suggestion is a very loose one: replace Umbreon with a Pokemon that's just as good or even better at sponging special assaults, that also functions in the weather. What Poke does that, ya ask?
... good question lawl
A sweeper with Calm Mind may benefit the team. Latias for example, (whom is not particularly the most useful for your team since your Ice and Dragon weakness would go up) would give your team even better Special bulk, another special attacker, and it'd still be a sweeper like your Umbreon. So yes, my one recommendation for tackling these problems is trying to find a Poke that has REALLY good synergy with the team, as Umbreon isn't particularly synergistic as far as I can tell.
One final bit I want to mention, is the slight abundance of less-than-perfect accuracy moves. Yes, I know I ****in' suggested like three said low-accuracy moves to replace moves that had perfect accuracy. ¬_¬ But it's just somethin' to always keep in mind when designing/playing a team. Missed moves add up to lost momentum or a full-on disadvantage very quickly, especially when playing against an offensive/hyper offensive team. "Minimizing the chances of bad luck increases your chances of good luck; or better yet, not needing luck at all". I'm not tellin' you to **** with your entire team because you have some imperfect accuracy, I just wanna mention it simply because. It's an important tip every competitive battler needs to know. I'll end up tellin' it to everyone in a review at some point, even if said trainer doesn't have a ton of inaccurate moves lol.
Regardless of all these points, I still think the team is definitely good. You have weaknesses, but they aren't "OMG I ENCOUNTER THIS, THIS, OR THIS THREAT AND I LOSE", said problems are both conquerable with skilled plays as well as fixable with some team tweakin'. Pretty good team, but it ain't fantastic. That's my rating of it as it is now.
By the way, we need to battle on PO ASAP. ... Hopefully I don't lose, since havin' a sneak preview of your team gives me a disgusting advantage. I'd be shamed beyond what I'd think possible.
Most definitely guts. Heracross ain't exactly fast, so taking advantage of paralysis/especially poison to give it a huge boost in attack makes it much more scary overall than a Swarm-boosted Megahorn. It also gives it an amazing immunity to Burn's attack drop. Swarm < Guts in pretty much every situation in competitive battling, minus a Reversal set (any status will either make it too slow to sweep, or kill it with residual damage before it can fire off said Reversal at full power). Not to mention Guts also works wonder with a SleepTalk set, making it scarier AFTER it absorbs some sleep for ya. Ain't too many other Pokes that can do that, yeah?
... It's good to be makin' huge posts again.