I've made seamless sleeves by altering a pattern. If you check out Brad Griffies, his dresses are done that way. I don't think I would bother if the sleeves were a solid fabric, but it is so much prettier with mesh sleeves not to see that dark seam. It wastes a bit more fabric because the front/back yokes and sleeves are all cut as one on a fold.
As for the sleeve point, if you square off the point, narrow hem the sleeve, then fold the squared off part around the elastic loop (or make your own by sewing a narrow tube of skin colored mesh), it is less fiddly and more secure. I cut my sleeves long, have the skater try it on, extend her arms and then mark them. It's an extra step but ensures they are perfect. I like to do a try-on before I put attach the skirt, lining, and leg elastic in so I can easily make final adjustments, so that's when I mark the sleeves.