Improve Indoor Coverage other than basic RF tuning

Hello Experts,
Generally speaking, what are the best practices to improve L1800 indoor coverage other than basic RF tuning (Azimuth, tilt, power… etc)?
Bearing in mind that no other bands are currently available.

Small cells or micro cells to reach 3-4 walls into office or enterprise.
Offloading is the best from Macro.

I see. So you’re suggesting deployment of small or micro cells, right?

Dense area or CBD or office is the one of the best one.

I see. Thanks for the contribution.
What do you think of deploying L900?
Currently part of 900M band is deployed on 3G, and since I still have U2100, I though of this.
Given that there is good percentage of terminal capability in terms of L900.

Avoid DAS since its 1T… better to use diff methods.
Upgrade SISO DAS to MIMO DAS: This has the advantage that capacity can be increased without using more spectrum.
This option could prove expensive if cabling has to be doubled up.
Or RF over ethernet.
Radio DOT option also good. 1/10 of deployment time.

L900 is super band for indoor for anyday if available.

Very good insights. Really appreciated @Sivas_Viswa! :pray: