If you can improve CQI Modulation will increase with same PRB / RB Usage and in same case (same PRB Usage) your MCS increase and TBS directly will increase and code rate directly increases as you can see on the table.
So following suggestion can improve your efficiency.
Reduce to interference
Reduce to unnecesary ho signaling via playing NCIO for late / early HO ,
Optimize to the CPUR among the bands ( Carrier Power Usage Rate etc KPI )
To balance the traffic among band depend on your bandwidth per carrier.
Check your Pa/Pb/referenceSignalpower/CellCHPower settings and if possible depend on bw , make sure you have same values among band depend on Bw.
Balance to the PRB Utilization among bands
Carrier aggregation activedelay thd , active buffer length thd etc. ( Huawei )
Activate the UlComp feature ( Huawei ) Coordinated Multipoint (CoMP): Explore CoMP techniques to enhance coverage, reduce interference, and improve spectral efficiency by coordinating multiple transmission points.
Activate Smart AMC feature ( Huawei ) Advanced Modulation and Coding: Utilize higher order modulation schemes and coding rates under favorable channel conditions to increase data rates.
Activate the cainstantlyjudgeswitch ( whether to use instantaneous millisecond-level values or filtered second-level values to evaluate SCell activation based on traffic volume. If this option is selected, instantaneous values are used. If this option is deselected, filtered values are used. / If this option is selected, SCell activation is more probably to be triggered. The procedure is initiated through MAC control elements, which are transmitted using low-order MCSs. If there are a large number of CA UEs, frequent SCell activations decrease UE throughput. However, for small-packet services such as web browsing and small-size file transmission, selecting this option ensures a higher probability of SCell activation, thereby increasing )
Cyclic Prefix Optimization: Adjust the cyclic prefix duration to balance the trade-off between multipath diversity and spectral efficiency.