For my weight/ riding style, I've gotten recommendations for everything from a 162-170... so obviously, my 154 is quite small...
The tip to tip cm length (162, 170, 154 from above) of a board in itself means very little in terms of performance. I would focus your comparisons on running length or effective edge.
Depending on how the manufacturer extends or blunts the raised tip/tail a much shorter board can "ride" longer than a much longer board. It is also very common for the "marketing length" of the actual product (the size printed on the board) to be far off from the actual board measurement. Take a tape measure to your current deck. You may be in for a good laugh
If possible let us know about the specific models that you are referring to / considering. That is the only way to make strong suggestions for you.