How about using acciaccaturas? Sure, you won't get exactly the triplet rhythms, but if you want those exactly you wouldn't use ornaments. This is how it would look:
You could use a pair of acciaccaturas each time with a single (quaver) beam, but the double beam seems more in keeping with the surrounding music to me, and suggests the rapidity with which they need to be played. You don't really need the slur either, but again it suggests that these notes are played rapidly almost as a single gesture.
The usage above is very simple, and would be particularly effective if the music is moving along at a reasonable pace (leaving little room between the semiquavers for anything rhythmically complicated). However, if the tempo is pretty slow, you could stick with your "exact" rhythmic notation, as a player would be more easily able to execute it exactly as you want it, with no ambiguity. If you choose to do this, you simply need to tidy up your beaming, to make it obvious where the beat groupings are:
Also, it occurs to me, that each of these decorative passages could either feel as though the quicker notes are part of the gesture along with the preceding tied note, in which case the following note feels somewhat accented, or as part of a gesture with the following note. Using a slur can help to make this distinction clear, if indeed there is one, so I have shown both types of slurring in the above excerpt.
Finally, @PatMuchmore makes a good suggestion, that the second of the two ornaments could be written as a mordent. By placing the mordent over the second half of the tied note, it should be clear that the upper note and return to the first note should be delayed:
UPDATE: I spent a while trying to find an example of this use of a "delayed" mordent on a tied note (see the comment discussion below), but haven't found one yet. Its rhythmic interpretation looks pretty clear to me, but unless somebody else can point towards an actual example of this usage, it should not be considered standard notation.