The Brazilian playmaker arrived from Inter Milan in the January transfer window and has impressed at Anfield with a series of eye-catching displays.
"He will be even better next season after the experiences of recent months and could be a really big player for us in the future," Aldridge wrote in his Liverpool Echo column.
"He's still being nurtured and he's learning all the time. Coutinho is still only a baby but he has great vision and ability to pick a pass. The little Brazilian is developing all the time and I love watching him."
The 20-year-old was signed for a reported fee of around £8.5m.