... I just was wondering how other Styles (Aikikai in General) further enhance and develop KI outside of waza. ...
"We" (Christian Tissier shihan / Endo Seishiro shihan; you will find examples of their/our aikido on youtube.) try to find "ki" and develop our "ki" and the understanding of it by practicing waza.
In very short terms:
If the posture of the body is "correct" ki will flow. If it is not good, there will be blockades an ki will not flow. So if you work on posture and movements you will get your ki flowing. If you get an understanding of what ist done this way and practice in this way, you will be able to "accumulat" and to concentrate your "ki". And you will learn to "direct" or "send" your ki willingly. Within your body. And you will be able to "extend" your ki.
Shorter again: Waza are ki exercises.
We seldom speak about "ki". Endo shihan more than Tissier shihan. But we "practice it".
In consequence (I think) our practice is much more "bodily" than I it seems to be in what I know as Ki-aikido.
Does this help a little bit?
Please be aware: This is not aikikai in general! This is just two teachers under this umbrella. And just my understanding of what they teach.