I have to admit, I've been long looking forward to writing a post with a title like that! But it has a pretty ordinary genesis.
Several days ago, I was sitting in a Brighton pub and discussing bust development with another trans woman. As one does constantly, of course, in a Brighton pub. I think the conversation drifted onto breasts from discussing the wider topic of fat deposits and midriff bulges - excess chubbiness being a frequent consequence of hormone therapy. Breasts are mostly adipose tissue, after all - that is, stored fat. And oestragen encourages its accumulation.
Anyway, we agreed that while a certain minimum breast size is very nice to have, too much flesh is a dismal curse, adding needless weight, making it very awkward to do anything remotely athletic, and possibly being a source of chronic backache. We agreed that having adequate bust definition is sufficient - that is, having shapely bumps that look natural when compared to one's body size. Nothing overblown, then, and certainly nothing so large that it would drive any natal woman towards breast-reduction surgery.
Many trans women will disagree about that, of course. Big boobs are most certainly the mark of a woman - and most certainly get away from any suggestion of a 'male' shape. Nobody can be blamed for yearning for 'statement mammaries', and the deep and definite cleavage that goes with them. We were simply acknowledging that small-breasted trans women need not feel inferior or hard done by. Small can be very beautiful, very practical, and lets you wear whatever you like.
But even among natal women there is this same worry over breast size. Shape is a big issue too. And not just the breast taken as a whole. Much fretting takes place over nipple size and shape, and the extent of the areola, that round patch of darker skin that surrounds the nipple.
At this point it might be best to provide a link with the Wikipedia article on female breasts - see https://en.wikipedia.org/wiki/Breast - which, if consulted, might confirm that any woman is likely to have breasts that are compromised in some way, from asymmetry perhaps; and that older women face other compromises, including sagging, which of course tends to stop breasts sticking out horizontally, and makes nipples point downward somewhat. Altogether a salutory read, if one is at all starry-eyed and unrealistic about the subject of breasts and nipples.
In this light, the usual small but pert 'teen boobs' that trans women grow may seem a rather better deal than often recognised. At least the tissue is recently-developed and of above-average firmness. So much so that on oldies like me, the boobs of (say) a fifteen year old look a thought incongruous. I should have sad, drooping sacks with stretch marks on them, and not these cheekily upright things. They will of course sag convincingly in time, but for now, I'd say they look unnaturally perky. Not that I'm really complaining, you understand!
As for nipples, these can for a long time seem small and unfeminine, and then they might suddenly expand and look much better. Mine did, anyway.
But there is no absolute size or shape for breasts or nipples that guarantees an 'ideal' appearance or measurement. Any appearance that resembles what a natal woman might naturally possess will be fine. Natural is good.
Trans women as a class are very hard to convince on this! So are natal women, especially young natal women, who ruthlessly compare themselves to other girls and find themselves lacking, or in some way highly unusual. Reassurance is needed. So far as nipples are concerned, have a look at this webpage: http://www.007b.com/nipple_gallery.php. The middle link at the bottom of that webpage will then take you to photos of breasts of all types, sagging ones included. Somewhere there will be a shot of normal breasts, or normal nipples, exactly like your own.
Nobody who is insatiably determined to have a big bust with protruding nipples will stop dreaming. But if you have run out of surgery-money, and can't even afford to keep buying progesterone on the Internet, and want to be satisfied with what nature alone has grown for you, then these pictures should help.