I think not all species are difficult to grow and rebloom. Most brachys (niveum, concolor, godefroyae, angthong), callosum, and cochlopetalums (liemianum, primulinum etc) are not difficult to grow, provided you understand their requirements. For a newbie, delenatii and niveum are not easy to distinguish. Both have sort of roundish leaves (as opposed to barbatum, which has pointed leaf tips)..
good luck trying.. Btw, delenatii is a bit picky and may not flower unless provided artificial cooling.