Yes. a larger rig will help you to plane alot more on the Rio (which size do you have...
For either of these larger sails you are going to need a longer mast (I'm guessing your 7.0 m2 Gaastra Pilot rigs on a 460 cm IMCS 24-26 mast, right?)
So, be sure to factor in the cost of a 490 cm (go for the highest carbon content you can afford as the difference in weight on masts longer that 460 can be substantial.
The NP V8 has always been a good choice for light wind performance.
I'd guess the North Warp is more of a racing sail and while larger, it's probably a bit more top end oriented.
Now, would I recommend either of these sails for a advancing beginner (2nd season)....
I'd suggest a camless (no camber inducers) 8.5-9.5 m2 sail (Sailworks Retro, Severne
Why, you ask?
Camber induced sails are a little more complicated, a little more difficult to uphaul, more difficult to rig, and you can get the same or better performance from the big no cams if you are looking for light wind early planing power.
If you have to choose between the 8.5 V8 or the 9.5 Warp, at your stated skill level I'd suggest the 8.5 V8.
Hope this helps,