While I believe it takes a while to effectively "combine" different arts seamlessly, I do see a great value in cross training. One of my biggest issues in Aikido is ukes who do not know how to attack effectively with good technique and commitment. A traditional style of Karate can be adventageous in developing good attacks, which are of great benefit for one's nage. Just make sure that you work to remain supple in your movements, and emphasise your ukemi in order to compensate for the power of your attacks. Sometimes people who come from a karate of TKD background are accustomed to rooting themselves, or may be a bit stiff.
Work to overcome that when training Aikido, so that your ukemi is sufficiently flexible to avoid frustrating you partner unneccisarily. Have fun!
Krzysztof M. Mathews
Every place around the world it seemed the same
Can't hear the rhythm for the drums
Everybody wants to look the other way
When something wicked this way comes
"Jeremiah Blues, Part 1"
Sting-The Soul Cages