Optimizing a view on multiple big tables

Question

I have many big tables with lidar data in oracle and I want to creata a view so my users can query them all in one place.

I made a view like this:

CREATE OR REPLACE VIEW SCHEMA.BIGVIEW AS 
SELECT 1 as JD_ID, PT_ID, PT_GEOM, Z_NAVD88
    FROM SCHEMA.V_TABLE1 
    WHERE CONDITIONS_TABLE1
UNION ALL 
SELECT 2 as JD_ID, PT_ID, PT_GEOM, Z_NAVD88
    FROM SCHEMA.V_TABLE2
    WHERE CONDITIONS_TABLE2
UNION ALL 
SELECT 3 as JD_ID, PT_ID, PT_GEOM, Z_NAVD88
    FROM SCHEMA.V_TABLE3
    WHERE CONDITIONS_TABLE3
UNION ALL 
SELECT 4 as JD_ID, PT_ID, PT_GEOM, Z_NAVD88
    FROM SCHEMA.V_TABLE4 
    WHERE CONDITIONS_TABLE4
--(...ETC, 22 TABLES LIKE THIS)
;

And it works but it's quite slow...

So I have 22 LIDAR tables/views with the same structure, each with their own WHERE conditions and many with millions of rows.

I wonder if there is a way to optimize this view (other than materialize it)? Thanks!