Here is a way to create a new AX table from C# (this is using an extension method):

public static bool CreateAXTable(this Axapta ax)
{
    string TableName = "MyCustomTable"; 
    string size = "255"; //You could load this from a setting
    bool val = false;
    if (!ax.TableExists(TableName))
    {
        AxaptaObject TablesNode = (AxaptaObject)ax.CallStaticClassMethod("TreeNode", "findNode", @"Data DictionaryTables");
        AxaptaObject node;
        AxaptaObject fields;
        AxaptaObject fieldNode;

        TablesNode.Call("AOTadd", TableName); 
        node = (AxaptaObject)ax.CallStaticClassMethod("TreeNode", "findNode", "\Data dictionary\Tables\" + TableName);        
        fields = (AxaptaObject)ax.CallStaticClassMethod("TreeNode", "findNode", "\Data dictionary\Tables\" + TableName + "\Fields");

        fields.Call("addString", "String1"); //add a string field
        fieldNode = (AxaptaObject)fields.Call("AOTfindChild", "String1"); //grab a reference to the field
        fieldNode.Call("AOTsetProperty", "StringSize", size);
        fieldNode.Call("AOTsave");

        fields.Call("addString", "String2"); //add a string field
        fieldNode = (AxaptaObject)fields.Call("AOTfindChild", "String2"); //grab a reference to the field
        fieldNode.Call("AOTsetProperty", "StringSize", size);
        fieldNode.Call("AOTsave");

        fields.Call("addString", "String3"); //add a string field
        fieldNode = (AxaptaObject)fields.Call("AOTfindChild", "String3"); //grab a reference to the field
        fieldNode.Call("AOTsetProperty", "StringSize", size);
        fieldNode.Call("AOTsave");

        fields.Call("addString", "String4"); //add a string field
        fieldNode = (AxaptaObject)fields.Call("AOTfindChild", "String4"); //grab a reference to the field
        fieldNode.Call("AOTsetProperty", "StringSize", size);
        fieldNode.Call("AOTsave");

        fields.Call("addReal", "Real1");
        fields.Call("addReal", "Real2");
        fields.Call("addReal", "Real3");
        fields.Call("addReal", "Real4");

        fields.Call("addDate", "Date1");
        fields.Call("addDate", "Date2");
        fields.Call("addDate", "Date3");
        fields.Call("addDate", "Date4");

        fields.Call("AOTsave");
        node.Call("AOTsave");

        AxaptaObject appl = ax.GetObject("appl");
        appl.Call("dbSynchronize", Convert.ToInt32(node.Call("applObjectId")), false);

        val = true;
    }
    else //Table already exists
    {
        val = true;
    }
    return val;
}


public static bool TableExists(this Axapta ax, string tableName)
{
    return ((int)ax.CallStaticClassMethod("Global", "tableName2Id", tableName) > 0);
}

I have created a query in the AOT and was able to use C# to return the data. Find the code below. It s a query that returns the sales that I create Aging Buckets with. I hope this helps.

[DataMethod(), AxSessionPermission(SecurityAction.Assert)]
public static System.Data.DataTable GetCustBuckets(String AccountNum)
{
    //Report Parameters
    Dictionary<string, object> d = new Dictionary<string, object>();
    d.Add("CustTransOpen.AccountNum",AccountNum);

    // Create a data table. Add columns for item group and item information. 
    DataTable table = new DataTable();
    table = AxQuery.ExecuteQuery("SELECT * FROM epcCustomerAging",d);


    DataTable tableBucket = new DataTable();
    DataRow rowBucket;

    tableBucket.Columns.Add("Current", typeof(double));
    tableBucket.Columns.Add("Bucket31to60", typeof(double));
    tableBucket.Columns.Add("Bucket61to90", typeof(double));
    tableBucket.Columns.Add("Bucket91to120", typeof(double));
    tableBucket.Columns.Add("Over120", typeof(double));

    //Variables to hold BUCKETS
    double dCurrent = 0;
    double dBucket31to60 = 0;
    double dBucket61to90 = 0;
    double dBucket91to120 = 0;
    double dOver120 = 0;

    // Iterate through the results. Add the item group to the data table. Call the display method 
    foreach (DataRow TransRow in table.Rows)
    {

        DateTime TransDate = Convert.ToDateTime(TransRow["TransDate"].ToString());
        double AmountCur = Convert.ToDouble(TransRow["AmountCur"].ToString());

        DateTime Today= Microsoft.VisualBasic.DateAndTime.Now;
        long nDays = Microsoft.VisualBasic.DateAndTime.DateDiff(Microsoft.VisualBasic.DateInterval.Day, TransDate, Today, 0, 0);

        if (nDays <= 30)
        {               
            dCurrent += AmountCur; 
        }
        else if (nDays <= 60)
        {
             dBucket31to60 += AmountCur ; 
        }
        else if (nDays <= 90)
        {
            dBucket61to90 += AmountCur;
        }
        else if (nDays <= 120)
        {
            dBucket91to120 += AmountCur;
        }
        else
        {
            dOver120 += AmountCur;    
        }
    }

    rowBucket = tableBucket.NewRow();
    rowBucket["Current"] = dCurrent;
    rowBucket["Bucket31to60"] = dBucket31to60;
    rowBucket["Bucket61to90"] = dBucket61to90;
    rowBucket["Bucket91to120"] = dBucket91to120;
    rowBucket["Over120"] = dOver120;

    tableBucket.Rows.Add(rowBucket);

    return tableBucket;
}

Here is an example of running a query in C#:

(Note: this is a very simplistic method by using an existing query definition, you could also build a query from scratch using QueryBuildDataSource objects, etc...)

    Axapta ax = new Axapta();
    ax.Logon("", "", "", "");

    //Create a query object based on the customer group query in the AOT
    AxaptaObject query = ax.CreateAxaptaObject("Query", "CustGroupSRS");

    //Create a queryrun object based on the query to fecth records
    AxaptaObject queryRun = ax.CreateAxaptaObject("QueryRun", query);

    AxaptaRecord CustGroup = null;
    ;
    while (Convert.ToBoolean(queryRun.Call("next")))
    {
        //GetTableId function is defined here: .Net Business Connector Kernel Functions
        CustGroup = (AxaptaRecord)queryRun.Call("get", ax.GetTableId("CustGroup"));
        System.Diagnostics.Debug.WriteLine(CustGroup.get_Field("Name").ToString());
    }
    CustGroup.Dispose();
    queryRun.Dispose();
    query.Dispose();

    ax.Logoff();
    ax.Dispose();

I honestly don t think it s possible to create new tables using the business connector. It has to be done within AX and the AOT.

As for returning mixed data, I would probably use a container object for that. Containers can hold sub containers, or axaptarecords. An AxaptaRecord contains data from one defined table.