You call yourself high for the empire place.I had an account with one wizard and he was lvl 73 in crustacean empire.He was a promethean when he was in ghost avalon.Now i pay less attention to side quests.I am now lvl 51 in the pyromancer's tomb.
I have a friend who completed Grizzleheim and Wintertusk right away, so when he was level 55 he was working on MooShu. THAT is too high a level. I think you're safe.
RavenLady is right. If you are entering CL at this level, it will be a very tough run.
If you have not done Grizz and Wintertusk, it will also make it harder for you to pick up certain spell and pet quests. Any of these that are missed will prevent you from getting the spell and pet quests in later worlds.
There is a lot of advantage to completing Grizz ( a little boring at times) and WinterTusk. The XP in Grizz is not that great but is much better in WT. AND WT is fun.
My balance is a level 65 and just now starting Stormriven in CL. My Life and Fire both entered AV at level 72+. If you have passed up a lot of side quests/worlds, you may want to go back and pick them up. They may seem trivial at the time, but it all adds up.
For those of you that may be running into some issues by being level 49 and 50 and entering CL, please check out the game updates for 2010 and especially 2011. Keep watch on the forums for additional information here and on Wizard101 Central.
Lucky, I don't do side quests at ALL! Never have. Therefore I am level 61 and I JUST entered Zafaria...
Being to much of a high level is a great thing to have because when you complete worlds you won't have to struggle to do side quests to get on to the next world in Zf. I'm level 58 wizard and I am struggling to get in to Zf
you are not smart you have to be 50 and up to get to any world above dragonspyre and if your ahead good as soon as you complete the final quest for that world you can be in the next world instantly but your in trouble cause your xp will go no where for a while and soon you be at the same rate as others
Actually, you only have to be level 48 and finish the quest "The Final Countdown" to enter Celestia
Well, I was level 48 when I got there, and I went like, oh wow, this is hard! So, I leveled up to get to level 50, and... it was still way too hard, so I just stuck to the side worlds, I won't be surprised if by the time I finish everything it would be STILL hard . Ahem, anyways to answer your question, no level is too high for celestia.
wizard and I am struggling to get in to Zf
you have to be 50 and up to get to any world above dragonspyre 
. Ahem, anyways to answer your question, no level is too high for celestia.