If you want a version without diacritics you can basically just use the Sorani Kurdish keyboard. I like the version with harakāt (diacritics) but haven't found a language/keyboard layout that lets me input the diacritics should I want to. The Kurdish version uses long vowels (full letters instead of diacritics) & even includes characters for e/o which are not used in Arabic.
ناسین سیتەلەن پەوی تاوا تۆکی پۆنا (nasin sitelen Pewi tawa toki pona)i/j ی
| a ا
k ک | e ە
(usually an 'h' in Arabic at least, but apparently is an 'e' in Kurdish. ێ is an 'e' sound also, but ە is mapped to 'e' key already)
l ل | o ۆ
m م | u و or ؤ
پ is the letter 'p'. ب is 'b'
ت is the equivalent to the english/tp 't' (ط is a 't' sound but further back in the mouth.) ت is more like in 'tick', ط is more like in 'tock'.
س/ت are phonetically more accurate for toki pona.
a=ا e=ە i=ی o=ۆ u=و
فَصُ لِ طَفَ
لِ لُكٍ عَ مُكُ صٍ
بِبِ لِلِ عُ
واسۆ لی تاوا لی لئکین
ە مۆکئ سین
پیپی لیلی ۆ
to remove some ambiguity & still be able to use the harakāt for vowels I would suggest ending one syllable words that end with a vowel with a long vowel. (و ۆ ی ە ا=a e i o u)
the full list would be:
la لا=ل+ا | ma > ما (instead of just ل and م)
'م' would be 'mun' (مٌ)
ل would be len (لً) or lon (لٌ)
With harakāt the poem would be:
وَسُ لی تَوَ
لی لُکٍ عَ مُکُ سٍ
پِپ لِلِ عُ
'a' could also be written as ا/اَ & ع/عَ for 'e' to distinguish the 2.
sin could also be written as سنْ، & sina as سن. The sukun ْ means there's no vowel following the letter it's attached to.
pan پنْ، & pana پن could also be written this way.
words with more than one syllable are more different so it wouldn't be neccesary to use vowels.
کپک can't be anything but kepeken کَپِکٍ.
ستل would be sitelen سِتِلٍ.
words starting with a would use 'ا'. words starting with e could use either ع/ە. For i/y you could use ی except 'ijo' would be یی/ییُ. u could be ع/و
esun= ٌعس/عَسٌ | ەس/ەس
ijo= یی/ییُ | عی/عِیُ
walo=وَلُ/ول | عَلُ/عل
alternatively you could add 'ا' after ً & ٍ as Arabic does s. wan would be وا/واً/وًا. Sometimes the diacritic is place over the 'ا' & sometimes over the letter before it (the real last letter of the word).