Best way to sync my iMac with my Macbook Pro?

iCloud can help you do that.

 

Try Google Drive. It has 15GB of cloud storage so it is not totally LAN dependent. Alternatively use the Time Capsule to store the libraries and point both Macs to it.

 

use software to sync the folders between two computers

FreeFileSync

 

Well, just move the iPhoto and iTunes libraries to the Time Capsule.

Then, on both the iMac and MBP, hold down Option when opening either iPhoto or iTunes. You'll then be prompted to select the relevant library.

 

Exactly this. There is little reason to have both computers share a single file stored on a time capsule when you can have iCloud automatically update and sync music and pictures between computers, iPhones and iPads.

 

That's the problem. That's why I said to move the iPhoto and iTunes libraries to a Time Capsule and refer my earlier post in the thread for the rest of the steps.

Don't use cloud syncing, you'll run out of space quickly.

 

For iPhoto and iTunes synching there's no better and hassle free method than iCloud and iTunes Match.
I have a 75gb plan for I cloud and the 25 dollar plan for iTunes Match.
If you have a music library of more than 25000 songs though the iTunes Match is useless for you. Unfortunately big libraries aren't supported.

And iCloud I think doesn't go higher than 100GB

So if you don't want to go through the trouble of cleaning up some of your old photographs than probably you should check out a different method.
But just to let you know for the thing you want your computers to do iCloud and iTunes Match is perfect.

 

Move files mac to mac

I am probably too late on this, but...
Google "copy music mac to mac". Read how to do it using home sharing with two macs Ethernet connected.
For photos, drag copy the iPhoto library file in the pictures folder one mac to the other. Slow but it works.
For later changes, I am sorry. The only way I know is to copy manually each new music or photo from master mac to the other.