You really should have a Water or Ice Pokemon with Ice Beam so you could own Lance quickly. Remember when you played Pokemon Red/Blue and Lance was very easy but when you moved onto Pokemon Yellow they improved him? I think Pokemon FR/LG is like this they have Natures and EVs to think about so Lance's Dragon Pokemon are super strong. Remember after Lance you'll have Green (Gary) to battle so you're going to need a lot of Pokemon to survive because Green is a few levels higher than Lance.