Avoid making all cron jobs together and other questions. Is it right?

After fixing some other issues I had with this plugin, I noticed that the db had many process related to post indexer.
I have 3 questions regarding the database load:
1. Will something like the following http://wordpress.stackexchange.com/questions/52989/how-to-set-up-multiple-cron-task-with-wp-schedule-event-so-that-they-do-not-over if used in function set_up_schedule() of cron.postindexerrebuild.php file. will reduce the database load?
2. Is it wrong to set postindexer_tagtidy_cron(), postindexer_postmetatidy_cron(), postindexer_agedpoststidy_cron to run once dialy instead of hourly?
3. If the PI_CRON_TIDY_DELETE_LIMIT, PI_CRON_TIDY_COUNT_LIMIT used in the queries can be set in greater number or complete left out in order to speed up the process?

Thanks in advance