Can I just put in a 150 or 200 amp service panel with 30 spaces? I won't be using more elect I just need the room to split things up a little more

Yes, make sure that the person changing the service is a electrical contractor.

No matter who installs the box, the main breaker can't be larger than the rating of the meter and incoming wire. I was looking at replacing my old 100 amp box with a larger one and installing a 100 amp breaker until I can get the power company to upgrade my service. Unfortunately, it looks like a 100 amp breaker won't fit the newer 200 amp boxes. It may be possible with some brands.

Labman, take any new panel, by GE,Sq D, ITE, and many others, use a 150 or a 200 amp Main Lug Only panel, but use a 2 pole 100 amp branch breaker in where a branch breaker does. Since it is a "backfeed" Main, you also need a retaining clip or kit. These are sold as breaker accessories.

You now have a 100 amp 30 or 42 circuit panel.