Lonely Nature isn't the worst possible nature for a Blaziken, but it also isn't the best. It raises Attack and lowers Defense, giving him a boost, but also increasing weakness to a hit he might otherwise survive. If this is okay with you, Great!
If not, you should breed this Torchic to get a better nature, such as Adamant. Once you get that, breed the one with the proper nature while holding an Everstone until you get the right IVs.