The linguistic meanings of creare and procreare are not the same: the latter contains a directional prefix, which indeed has a semantic contribution that goes beyond the meaning of 'in front of'. For example, according to García-Hernández, a Spanish Latinist scholar who has analyzed the very complex topic of Latin preverbs, pro- enters into an important opposition with ob-: e.g., vid. García-Hernández (1991): pro- vs. ob-. In particular, I like his image-schematic representation of Latin preverbs.
It is well-known that the path/directional meaning of Latin preverbs became grammaticalized into other more abstract notions (e.g., aspect; cf. also the "intensive" value attributed by Draconis in his answer). It is worth pointing out that, in the specialized literature, complex/prefixed verbs like procreare or producere are considered as good examples of the so-called "satellite-framed" nature of Latin: path/directionality (and aspect) is typically encoded in the preverb or particle (aka. "satellite") in so-called "satellite-framed languages" (e.g., Early & Classical Latin, German, Russian, etc.), whereas it is typically expressed in the verbal root in so-called "verb-framed languages" (e.g., Catalan, Spanish, Turkish, Japanese, etc.).
Accordingly, a typical linguistic analysis of Latin complex verbs like procreare involves (i) to consider the preverb pro- as the so-called "framing event", i.e., as the main predicate and (ii) to consider the verbal root as the so-called "co-event", i.e., as the subordinate predicate. So procreare (originally) means something like "to bring forth by creating". In contrast, the meaning of creare is obviously less complex since it lacks the path/aspectual meaning attributed to the prefix.
For readers interested in this complex topic of Latin linguistics, here is a recent reference: Latin as a satellite-framed language. Among other interesting things, this author shows a very important parallelism between Latin and Slavic languages (both are classified as "satellite-framed languages" in Talmy's famous typology: A typology of event conflation). Typically, when dealing with verbal prefixation in Latin and Slavic, the prefix expresses the main semantic idea, whereas the verbal root expresses the subordinate one (something similar to the English "out-prefixation construction": e.g., John {outran/outdanced/outdrank/outworked/...} Mary; lit.,'John surpassed Mary by V-ing' (cf. the lexical subordination meaning of procreare above). As noted above, this is also quite typical of other satellite-framed languages like Russian (e.g., see https://www.researchgate.net/publication/248315875_Verb_prefixation_in_Russian_as_lexical_subordination ).
