The definition in Commons Annotation Vocabulary is not a mere copy of what's in DCT with the documented addition of making it a owl:AnnotationProperty, but adds the triple :
<rdfs:subPropertyOf rdf:resource="&skos;note"/>
That may or may not be a good idea but it adds a dependency and it's a significant change that should be flagged.
In fact, given that SKOS itself makes use of DCT, that makes for a somewhat undesirable circular dependency though not formally stated.

If an aim is some sort of unification then maybe skos:definition should be made a subProperty of dct:description.

Wrong property used for collection members in restrictions on List and ChronologicallyOrderedCollection.
These make use of hasConstituent but this is disjoint with hasMember and it says "This property is disjoint with hasMember, and should be used in cases where the constituents of something are not considered discrete elements of whatever they are included in, such as a substance or composite."

The definition of List includes "set of related items"

Little best practice or guidance is given in either the spec or the ontology. By the fact that they're included it seems that skos:prefLabel and skos:altLabel are recommended. However they're not actually used in this or any of the other Commons ontologies.
Commons itself provides an alternative with its Designations ontology. And OMG provides a strong capability in MVF.

Users of Commons should be warned about the anti-pattern use of rdfs:label as the primary in conjunction with skos:altLabel which makes it impossible, with reasoning enabled, to return only the primary (since skos:altLabel; is a subProperty of rdfs:label)

The definitions taken from SKOS seem altered and incomplete.
For example here is the official definition from SKOS RDF file for altLabel. The Commons version changes the label (using "tag" instead of "label") and omits the comments, one of which is the important (informal) disjointness constraint, and example.

<rdf:Description rdf:about="#altLabel">
<rdfs:label xml:lang="en">alternative label</rdfs:label>
<rdfs:isDefinedBy rdf:resource="http://www.w3.org/2004/02/skos/core"/>
<skos:definition xml:lang="en">An alternative lexical label for a resource.</skos:definition>
<skos:example xml:lang="en">Acronyms, abbreviations, spelling variants, and irregular plural/singular forms may be included among the alternative labels for a concept. Mis-spelled terms are normally included as hidden labels (see skos:hiddenLabel).</skos:example>
<!-- S10 -->
<rdf:type rdf:resource="http://www.w3.org/2002/07/owl#AnnotationProperty"/>
<!-- S11 -->
<rdfs:subPropertyOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#label"/>
<!-- S12 (not formally stated) -->
<rdfs:comment xml:lang="en">The range of skos:altLabel is the class of RDF plain literals.</rdfs:comment>
<!-- S13 (not formally stated) -->
<rdfs:comment xml:lang="en">skos:prefLabel, skos:altLabel and skos:hiddenLabel are pairwise disjoint properties.</rdfs:comment>
<!-- For non-OWL aware applications -->
<rdf:type rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"/>
</rdf:Description>

SBRM and other OMG processes need to be able to connect documents to the components therein. RTF members have requested that we add these terms to the documents ontology to facilitate mapping to other document ontologies as well as for extension purposes.

Several OMG members have requested a general ontology that includes sites and facilities, which are currently modeled in FIBO, primarily for lending and asset management purposes, but they are also needed for retail and manufacturing. The relationship between a site and a facility is many to many, and modeling them for manufacturing as well as retail, energy, military, and other domain areas can be tricky. Having the general pattern that can be extended by any domain area would be very useful for extension purposes.

Commons is missing a class representing a simple ordered list of items. The class StructuredCollections:List is far too heavyweight for general use:
Each member must be an IndexedConstituent which in turn must have a value for comprises which is an IndexValue defined in an IndexingScheme and only that actually refersTo a nonNegativeInteger.
      myList a :List ;
      :hasMember [
            a :IndexedConstituent ;
:comprises [
a :IndexValue ;
:characterizes <member1> ;
:isDefinedIn :myScheme ;
:refersTo ??;
:hasNumericValue 1
]
           ] ,    
           a :ListMember ;
            :refersTo <member3> ;   
            :hasSequence 3 ;
           ] ,    
           a :ListMember ;
            :refersTo <member2> ;   
            :hasSequence 2 ;
           ]    
.
That might represent a StructuredElementList but for a basic list one would only need one class and two properties - something like:
      myList a :List ;
      :hasMember [
            a :ListMember ;
            :refersTo <member1> ;   
            :hasSequence 1 ;
           ] ,    
           a :ListMember ;
            :refersTo <member3> ;   
            :hasSequence 3 ;
           ] ,    
           a :ListMember ;
            :refersTo <member2> ;   
            :hasSequence 2 ;
           ]    
.

The class ChronologicallyOrderedCollection is unclear when it says "structured collection whose elements are ordered by time", since the elements are more than simple (time) values but individuals with potentially many properties which are time-related. Even for the example given of bank transactions there's often a difference between the time the transaction happened and when it was recorded: my credit card statement has both "Post Date" and "Trans Date" - with the statement ordered by Post Date. And in some cases the time-related property might be on a separate linked individual. For some cases it could get a lot more complex e.g. employment for a person - there might be period overlaps.
Even ChronologicallyOrderedConstituent does not help - it seems to select only hasObservedDateTime which is both over-specific (how does it help with Employment?) and still under-specified (since hasObservedDateTime is itself pretty vague "indicates a date and time associated with an event, measurement, record, or observation" which does not discriminate the above examples or help with Employment).

Ontology StructuredCollections adds properties to Constituent which tend to add confusion rather than value. Specifically it adds a synonym "element" with explanation "an element is part of a set..." yet a set is by definition unstructured - the opposite the whole purpose of the ontology which is structured collections

It's counterintuitive that the class StructuredCollection is not in the ontology StructuredCollections. It breaks the naming pattern that an ontology is named after its principle class.

There is a gap in the quantities and units ontology whereby we cannot represent counts of things, which do not necessarily have units, nor can we properly represent ratio values, which may involve scalar quantity values that do not have units. There is also a challenge in representing ratio values more generally, since there is no numeric value representing the ratio on the class.

This is needed for representation of tensor and vector quantities for the quantities and units ontology, and for representation of certain machine learning algorithms, among other requirements.