emindahken phoneme list

New conlang:
emindahken -- spoken by human-type beings on another planet (don't have
much more in the way of conculture, other than that they are not
technologically advanced as we and they live in mountainous terrain).

VOWELS
close: [i]; [I]; [u\]*; [u]
close-mid: [e],[2]; [8]**; [o]
open: [A]

* I may mean [y] here, which to me is like an [u] moved to the front.
But then perhaps [u\] is what I had in mind.
** Is this the representation of the German (sorry, no dialectal
knowledge here) o-umlaut?

Long vowels:
[A:], [e:], [o:]
Diphthongs (palatalizations really) allowed:
[A_j], [A:_j], [e_j], [e:_j], [2_j], [o_j], [o:_j], [8_j]
Phonological constraints:
none at the moment, but likely to appear.

Questions:
Is this naturalistic? If not, how can I improve it?

CONSONANTS
plosive: [p],[b]; [t],[d]; [k],[g]; [q]; [?]
nasal: [m]; [n]
tap/flap: [4]
fricative: [f],[v]; [T],[D]; [s],[z]; [x]

Additionally, I have the following palatalized consonants:
plosive: [t_j],[d_j]
nasal: [n_j]
fricative: [s_j] (which I think is actually [s`]), [z_j] (probably [Z])

Phonological constraints:
No clusters allowed except for /st/ at the moment.

Same questions as for the vowels.
Thanks,

--
=============
James Worlton
          "We know by means of our intelligence
          that what the intelligence does not
          comprehend is more real than what it
          does comprehend."
                           --Simone Weil