After trying and testing a lot on PO, I have finally managed to work out a team. Now my team is able to counter many of the new threats but is still lagging against some crucial ones, especially the sun teams a bit.. So I will appreciate all sorts of advises here.
Also, Because of the Team Preview, I do not have any fixed Team Lead.
EDIT : After the suggested advises, I have made many changes in my team, just for instance introduced a better staller, and took out some boosting pokemons. I have then tried to test my changes on PO, and they are giving me more sound results. But I still lack somehow, and I want a full RMT now, so that I know how to perfect my team more.
Heres My Team :

Tentacruel (F) @ Leftovers
Trait: Rain Dish
EVs: 252 HP / 236 Def / 20 Spd
Bold Nature (+Def, -Atk)
- Toxic Spikes
- Rapid Spin
- Scald
- Protect
This one is far more better than the previous one, as it now take full advantage of rain (if I am opposing a rain team).
Great Spinner of my team, lays toxic spikes in many switch ins and burns the remaining pokemon with scald.

Gliscor (M) @ Toxic Orb
Trait: Poison Heal
EVs: 252 HP / 184 Def / 72 Spd
Impish Nature (+Def, -SAtk)
- Swords Dance
- Earthquake
- Protect
- Ice Fang
Same, I have not changed it. Takes terrakion, conkeldurr, heracross, scizor, breloom, and the pink sisters namely chansey and blissey (as it do not fear status) quite efficiently. The only Booster remaining in my team now.

Scizor (M) @ Choice Band
Trait: Swarm
EVs: 252 HP / 252 Atk / 4 Spd
Adamant Nature (+Atk, -SAtk)
- Bullet Punch
- U-turn
- Superpower
- Pursuit
Changed from swords dance set to choiced set. Take on lati@s quite efficiently now, and has a good synergy with heatran. Though I think, would it do me any good if I invest some in speed to outspeed heatran and with U turn, pop his balloon, and give control to my own heatran who can now OHKO him with earth power and might get a fire boost too, if mispredicted by opponent???

Shaymin @ Life Orb
Trait: Natural Cure
EVs: 4 HP / 252 SAtk / 252 Spd
Timid Nature (+Spd, -Atk)
- Seed Flare
- Earth Power
- Hidden Power [Ice]
- Rest
My brand new pokemon, who now works very well against rain teams, and help the team by absorbing unwanted status (with my own conkeldurr gone now for that purpose). Works well with cresselia, who paralyze the opponents, so that he can rest when he is at the edge, and switch back and in to wreak havoc once more. Shaymin saved me from a lot of hassle by countering vaporeon efficiently, and checking the pink sisters. I have invested heavily in speed so that he outspeeds nearly every pokemon, like gliscor, haxorus etc. and OHKO with HP Ice.

Heatran (F) @ Air Balloon
Trait: Flash Fire
EVs: 252 SAtk / 4 SDef / 252 Spd
Timid Nature (+Spd, -Atk)
- Fire Blast
- Earth Power
- Hidden Power [Grass]
- Stealth Rock
Another new one, though not that new as I mentioned my change over volcarona in one of my posts later. Works well against sun teams, and perhaps the only one that has a chance against sun teams. If he gets knock out, I Loose pretty much easily. Has a great synergy with scizor, and both work hand in hand for each others counters.

Cresselia (F) @ Leftovers
Trait: Levitate
EVs: 252 HP / 252 Atk / 4 SAtk
Bold Nature (+Def, -Atk)
- Reflect
- Thunder Wave
Another brand new, and replaced celebi (celebi replacing magnezone prior to this). Works well with shaymin and especially gliscor as she paralyze the opponents and have gliscor set up well. Reflect and thunder wave are like two status together : burn and paralyze with former having only no residual damage. Blends perfectly well against Salamence, Haxorus and Dragonite. Sometimes it helps me against Gyardos also.. But best support for my team as of now..
Though these changes have surely eliminated some of my old threats, I have now acquired some new threats. With conkeldurr gone, gyarados tears through my team. Venu is still a great problem to me. I have lost some good revenge killers making chansey more profound if her teammates manages to knock my gliscor. I now request for a complete RMT of my team, if you can..
Its my first RMT, so please bear with me.. I appreciate all types of constructive comments.. A Complete In-Depth RMT Will also do..