These are very good for student work. Obviously the training you've done is paying off and you've put a lot of work into these photos. i don't think they are boring at all-- they are much more overt and "out there" than most erotica, which in general will appeal to more men.
NJQT pointed out that the background was a bit distracting in the first one, but there's a really simple way to correct that. I did a wedding this year where the walls were hung with mural-sized paintings and what we had to do was move the subjects away from those backgrounds to make them a little darker than the subject and slightly out of focus by using a limited depth of field. it made that kind of background work. i'd also increase the contrast a little, and it looks like you added some soft focus which you may want to back off except to use selectively for some skin smoothing.
the second one is the best of the bunch in my opinion. the lighting is good and the contrast between the warm skin and the cool background works well.
the third and fourth ones don't really work for me all that much. that particular look is something you need to shoot for ahead of time, and it's very hard to get the right lighting to make it work. it's very in style right now, but to do it right takes some planning and a little luck. i can tell from the photo that looks like it's from the same series that's color that your background was totally blown out, and that's something that's really hard to correct and even harder to make work compositionally. I don't know if you're using lightroom or photoshop, but there's a recover function in lightroom and highlight/shadow in photoshop that might help bring back some of the detail. in the black and white ones you're losing a lot of edge detail which is the only way to make that particular look work. i've yet to have a photo i've been happy with using that look.
the sepia is really nice, i think your instinct to make it sepia was a good one. the highlight on the breast is really bright, and if you go to print it out you're going to get some bronzing on the edges because there's no detail in it. that's not hard to fix though.
the one after is nice. i might add a very slight fill for the back or move the light around a bit, but nothing huge. it's really a sexy shot and it's suggestive rather than overt, which i really like. there's a sense of a story in it, of a captured moment, which is really good.
the grrr one has a nice look to it, but the lighting is a bit uneven, making the face look very white, the skin to the breasts look dark, and there's a line of shadow across the breasts where the nipples are that makes the rest of your body completely in shadow. i think the light isn't the most flattering for bodies-- you want to accentuate curves over lines.
all in all, i think you're making a good start. the one thing that concerns me is that you're planning on doing these photos for "mums and old ladies" and you're going to find that the challenge of making these type and glamour shots for them is going to be very difficult, both shooting and editing. you are lucky that your body and face need little correction-- but fixing dimpled asses and thighs, crows feet, etc. etc. can be harder than you expect, especially if you're using the more direct kind of light that you've used in these photos. i use a lot of natural light because diffuse, indirect light that's not flat really flatters most everyone.
you may want to look into getting a ring flash if you're planning on doing this professionally. used with other lights, a ring flash can make a huge difference in molding contours on the body and in the face. if i did more actor/model/glamour/erotica that's the first thing i'd invest in.
if you're seriously considering doing this as a profession and you want to make really excellent work, see if you can get into assisting other photographers and sitting in on their shoots. i still do this and it's been the best way to learn for me. making contacts and working with other photographers can really help you get over than hump from being a student/advanced amateur to a pro.
you might want to spend a year or so doing this and building your portfolio before you start making this into a serious business if that's your plan. if it's just a hobby for some pin money, that's a little different. you're going to want to make your pricing reflect that and probably stick to friends and acquaintances because people can be merciless when it comes to spending their money, especially when looking at photos of themselves where they see every flaw (and some imagined). i still do work for free for friends to build my portfolio because it gives me more leeway to experiment which i can take to my paying jobs.
good luck with this! you've got a good start. if you ever want to talk about photo more, PM me. i'm sure we'll both get something out of it.