I like a 15 card spread that involves five groups of three. Four groups of three with each group at a corner, with the fifth group in the center.
This spread was originally thought up by Alister Crowley, but that's no reason to think less of it.
You can pretty much decide what you want the cards to be... for example, I tend to think of the centeral card grouping to be telling me what is up in general for the querant. With past, present and future going from right to left.
Then the right side is the past and the top being what happened and the bottom being what is suggested, hidden, or other metadata worth knowing.
On the left, you have the future, with the top being events or people and the bottom being the metadata, such as suggestions, comments, or hidden information.
I also find that this spread gets fluid, I'll realize that the top and bottom parts of the spread are talking about two different outcomes, when the past is mostly about the choices that the querant has had to make so far and why.
But it's this flexibility that brings me back to it again and again. Just remember that there's always a story in this spread, and that the center is the person most closely involved with the question, often the querant themself.
I will also use this spread to explore multiple options for a course of action, or to find out what I'm not hearing about a given situation.
I too don't like the celtic cross. I find it rather unflexible.
Now, I also use a spread that I call The Gate spread. it's a box very much like this one, only its a card above a card on each side a card below and one in the center. I use it mostly for meditation and for a quick overview of a situation I need a briefing on. Above is always what you aren't seeing. (ask a soldier... people just don't look up) Below is what is the foundation of the situation, sometimes the past. Hidden stuff can be here, too, since people don't always look where they are going.
The stuff to the side can either be past on the right and future on the left, or it can be supports or blockages for the path. (go forward, or go back?) The center is, of course you or the querant or the situation at hand. The above card can also be things like spiritual guidance or what the Wyrd has to say about things.
I also feel compelled to mention that cards that fall out of the deck while you are shuffling are always trying to tell you something. But it's guidance to you, not to your querant. If you are asking about you, of course, it's free advice, or things to think about while you are doing the reading.