RE: increase report usage for CPU
If you experience any kind of slowness in AX including reports, that is rarely related to CPU/Memory issues. In 99% of the cases it is linked to SQL Server, or code design problems.
Make sure you have regular index/statistics maintenance, SQL Trace flags are set as per the recommendation for Dynamics AX, your disk layout for data and log files and number of TempDB files per NUMA core are correctly created, etc.
As for the code design, Crispin has already mentioned the possible solutions. If you feel that a particular report is slow because it is query-based, or using temporary tables, try optimizing/redesigning it, or convert it to pre-processed report.