i can't stand the new elantra, i drove one, hated it.
also, the focus is a much more expensive car, heck so is the mazda3 at the top of the line.
do they offer more features? sure. do they cost more? yes.
same goes with the SI vs the ms3/focus ST... the SI really is a niche itself... a quick, sporty, affordable NA high revver that returns good fuel economy and comes in a sedan or coupe variant... the ST is hatch only, as is the MS3 (which i like, but some dont), also they are turbos, some people don't want that.
same goes for the GTI and WRX, both turbo, which some folks don't want.
probably one of the main reasons the SI hasn't been significantly "improved" is 1) it was so far ahead of the competition a few years ago, they've merely "caught up" and only passed the SI slightly, if at all in some cases... and 2) nothing really competes directly against it
heck even the Veloster turbo, which hyundai takes a straight shot @ the SI in their press release a few months back, is a turbo.
i'll name the top cars under 30k in the "hot hatch/pocket rocket" category (no particular order)
1) subaru wrx - 25k base, reaches 30k+ loaded - turbo - 4dr hatch/sedan - low to mid 20's fuele con
2) mazdaspeed3 - 23.5k base, 26k loaded (i think, too lazy to look) - turbo - 4 dr hatch only - low to mid 20's on fuel econ
3) vw GTI - 25k, 30k+ loaded - turbo - 2dr/4dr hatch - high 20's to low 30's fuel
4) vw GLI - 25k, 30k+ loaded - turbo - 4dr sedan - high 20's to low 30's fuel econ
5) mini cooper S - 25.5k base, well over 30k loaded - 2dr hatch - turbo - high 20's to low 30's fuel econ
6) hyundai veloster turbo - 22.5k base 25k loaded - 3rd hatch - turbo - high 20's to mid 30's fuel econ (i refuse to believe hyndais claim, as real world are getting mid 20s)
7) focus ST - 25k base 30k+ loaded - 4dr hatch - turbo - high 20's to low 30's fuel econ
8) civic si - 23k , 25k nav (only option) - 2dr coupe/4dr sedan - NA - high 20's to mid 30's fuel econ (slightly better than GTI)
honestly, while they are all direct competitors of the SI for comparisson sake, none are NA engines, which some people prefer, which is why i think the SI has become semi "stagnant" in it's progression, though i'm extremely satisfied with mine!!
any other vehicles i missed in that range let me know (v6 mustang/camaro don't count, they aren't generally cross shopped in the FWD [awd for subaru] hot hatch/pocket rocket segment)