Dear Dr Micovic,
Being myself a convinced Platonist convaincu, I read your essay several times and really with great pleasure.
I totally agree with you that anti-Platonistic approaches - materialist approaches and other - are as metaphysical as Platonism. In my own essay, I insist further on this point, since this latter does not seem obvious to everyone. Many people continue to think that only the consideration of material reality can be "scientific" whereas any hypothesis on the objective existence of immaterial entities, such as mathematical entities would be "exactly the kind of metaphysics" that scientific thought should ignore. I'm still totally agree with you that all we can do is comparing all metaphysics involved in the debate about mathematical foundations and links between mathematics and physics, in order to determine BEST metaphysics in the scientific sense of the term "best". Here, the evaluation of competing metaphysical theories must respond to epistemological criteria such as economy of hypotheses, logical simplicity, consistency of the theory particularly with regard to its consequences and so on. Under these criteria, Platonism is indeed the best metaphysical approach of mathematical foundations and the link between mathematics and physics. Certainly Platonism requires heavy hypotheses, but the hypotheses required by competing theories being not less heavy, attain by contrast a clearly higher degree of complexity. Platonism encounters serious problems, but the problems of anti-Platonistic approaches are much more serious.
It is absolutely plausible to establish a link between the Platonistic timeless conception of a mathematical world and the concept of block universe initially suggested by relativistic constraints. But you notice rightly, that there is here a risk of tension between the classical block universe and the idea of time flow; an idea which, despite its problematic side per se, can not simply be swept away. Being myself on a paper involving a bloc universe - it is to reconcile timelessness of idealized physical laws and de facto irreversibility, knowing that against "intuition", "common sens", "evidence" and so on, irreversibility IS NOT the direct negation of reversibility; this point is briefly touched in my own essay - I will read attentively your publication on arXiv about a Cauchy 3D hypersurface splitting of bloc universe. Personally, I envisage a superposition of a metric space with +++ - signature to an underlying non-metrical 3D topological space with a fibrous structure. The business looks complicated and I hope your arXiv publication which I unfortunately ignored until this moment, will be helpful.
Regarding both GIT, I think - by relying on Gödel himself - that they do not necessarily pose a problem to scientific Platonism. I published a paper on this issue in the magazine Al Mukhatabat; electronic versions are available on academia.edu (https://www.academia.edu/5262261/Syst%C3%A8mes_formels_et_syst%C3%A8mes_formalis%C3%A9s) or philfree (http://www.philfree.org/ecrire/?exec=article&id_article=545) But it is in French. Here, I try just a short, sometimes more metaphorical statement.
You notice rightly that GIT-undecidabilities can be avoided iff the concerned system Sy1 is imbedded in a "stronger system" Sy2. But within Sy2 we have once again this same undecidability, so that Sy2 must be embedded in Sy3, and so on ad infinitum. Now arises the following question: Can a système Sy(inf) possessing an "infinity of appropriate axioms" be sheltered from GIT-undecidabilities? This question is in turn undecidable. Its only formulation would never be admitted unanimously. A fortiori, one can neither prove nor refute the validity of Both responses "yes" and "no".
Gödel believes that the correct answer is "yes". It is a metaphysical belief and Gödel does not say otherwise. But the answer"no" est in turn a metaphysical belief. So we need to compare the two options in terms of gobal consistency. Gödel, starting from his hypothesis of an undecidability free system Sy (inf), thinks, that incompleteness and undecidability arise from the fact that all human knowledge of Sy (inf) is necessarily partial, so not only incomplete but also distorted. Both GIT would be only the consequence of this fundamental problem.
Now we can carry similar reasoning regarding "material world". Certainly, the main stream philosophy of the moment claims that the material universe does not know infinity.
Well, let us admit that there is only a finite number of phenomena, and that the number of cases where these phenomena occur, is also finite. But nothing prevents us to consider at least potentially the possibility of an infinite number of combinations of these phenomena. And even if some among us really do not want to admit this, we are still all in agreement that human knowledge masters just only a small part of the aspects of the material universe. This should not prevent us to postulate the existence of the material universe in all its details. Note in passing that this postulate is in turn metaphysical, and that the other postulate concerning the existence of the Gödelian undecidability free Sy (inf) is neither more, nor less metaphysical.
But anyway, our knowledge of mathematics is necessarily incomplete, so distorted. Its the same regarding our knowledge of the material universe. Both types of incompleteness can then join. On the other hand, the exploration of the mathematical universe promotes a better understanding of the material universe and vice versa.
It seems possible to construct on these bases a Platonistic epistemology being more consistent than its competing theories requiring hypotheses much heavier and much more complex.
In this regard I recommend you the excellent essay of Christine C. Dantas, as I recommend her yours. http://fqxi.org/community/forum/topic/2373
It would of course be a great pleasure for me to know your opinion on my own essay addressing Platonism in a different way. http://fqxi.org/community/forum/topic/2356
Best regards and good luck