Rhubarb isn't a bad option for Spring once you open up the Desert, it's only slightly behind Melon in generating g. Of course then you have Starfruit for Summer as well which is the best in the game, and then compared to Fall Rhubarb sells for 69% of Pumpkin so they're not super far behind.
Comparing Rhubarb to Strawberry with Deluxe Speed Gro, you get 3 Rhubarb and 6 Strawberry per tile in Spring. That's 1452g vs 1584g or 92% of the g with Rhubarb. Ah but the Seeds are 100g for each, so that becomes 1152g vs 1484g or 78% of the profit.
Rhubarb is a pretty good Spring Crop and I wouldn't be surprised if CA made Strawberry Seeds more accessible that the price would go up.