The plant on the right, on the driftwood looks to be an anubias and they are very slow growers. I have one in my 55g with 2.4wpg and it still grows slow, so IMO
more light won't really speed it up any. I can't tell what the other plants are. The one to the left of the crypt looks like a sword. I don't think they are terribly fast growers either.
If you replace the acitinic bulb, you will still be in the low light category. Most people say that an acitinic bulbs gives you only half the useable light, so that would mean you have just under 1 watt per gallon now. Replacing the bulb will only give you just over 1wpg, so not much difference.
The red crypt looks great by the way. Really big.
If you are interesting in getting a higher watt fixture, I have this one
over my 29g. It gives me just over 2wpg and I can grow medium and some high light plants very nicely.