If it is is pretty much stock, then your float level should be good. I am going to guess it idles well and pulls well otherwise?
Might not hurt to read up on 2 stroke carb tuning and make sure your air screw is properly set. It plays a big role in throttle response when coming from 1/4 throttle or less.
There is a ton of info and learning that you can find by searching here on the forum.
I would definitely getting the Blaster service manual either in print at your Yamaha shop or you can find a link to the pdf n here.
And Herp has a point, even stock the blaster has more than enough power to stand up in second.
Use your low pressure guage to drop the rear tire pressure down a little closer to minimum, and if your light drop the spring preload ( the 2 nuts at the bottom oF the rear shock. Move them down to decrease preload).
You can also play with the preload adjustment on the bottom of the front shocks, a tighter setting may bring the front up an inch or so but to high and you won't get aNY extra lift from the front to help get it up.
It will take a little extra guts but keep both feet on the pegs (in case you need the rear brake) and use that clutch to stand it up in second should be easier to control the balance, you may still run out of steam before you get it balanced where you can keep it up.
Often it helps to use a hump or a little lip like coming into the yard from a gravel driveway. That way you can hit it a little faster and get it up easier. If you can get it up in third should be able to ride wheelies pretty easy. A slight uphill grade will help you to keep it up without going too fast.
When I was a little younger I was able to use the terrain to get up a try 300 4 x4 and could ride wheelies as long as I wanted.
Practice, practice, practice and it will come.
Also, consider a high flow air filter, removing the air box lid, and getting a low end pipe, any or all of these will let more air in the engine, so you must rejet your carb to match.
Good luck and don't be afraid to set it on the grab bar
Deebee