If you don't mind using a seraph robe or draco shield on Meg, she can be raised fairly easily considering how few characters you will be using in Part 1. With a max MT and slightly higher than normal Hit forge, she can normally 1-2 round the laguz in her starting chapter. Sit her next to someone like Laura so she can heal and put her at a choke point and you'll probably end up with a decently leveled, completely usable Meg who mainly suffers from her horrible move. While Fiona does have an amazing endgame, it takes a great deal more effort to actually raise her to a reasonable level (without using a lot of BEXP which ruins her great growths) and I wouldn't bother trying with her. Illyana alternatively is very useful since you only have two dependable 'chip' damage users in part 1. While I wouldn't attempt to raise her to endgame, when she is around it would be a waste not to use her.
