My mistake. I was thinking daylight riding lights in the US was headlight. If the headlight was only used for an hour or so each ride could I get away with more wattage.
Some states require the headlight on while riding. Some bikes have a lighting switch and others don't. All the F bikes don't if stock.
You know you can't really bargain with physics, it is what it is.
Depending on how you ride, yes you can get away with more wattage.
Think of your battery as a bucket with a hole in it. Whenever the key is on the hole is exposed and the bucket starts draining.
The alternator pours water back into the bucket, trying to keep it full. But, at low RPM the water going to the bucket is less than what is coming out the hole.
When the alternator CAN put more water in the bucket than is draining out it can fill the bucket to overflowing. The regulator keeps the bucket from overflowing during these times by reducing alternator capability.
A higher wattage headlight is like putting a larger hole in the bucket. At low RPM the bucket will drain faster than before. And when revved, the bucket fills more slowly, and takes longer to get full.
If you keep the engine revving always, the battery will stay full, provided you haven't totally exceed what the alternator can provide in best case with a huge headlight load.
Certainly when the headlight is off, the charging system can maintain a full battery. Whether, it can while the headlight is on depends on the riding regime and the extra load introduced.
If I knew what percentage of your headlight on regime was at 5000 RPM, I could estimate. But, if you ride home at night and spend too little time above 3000 RPM with a big wattage headlight, the battery may not be fully charged at shutdown.
Hope this helps,