You have a couple options ...
1 - figure out what's using up your object descriptors and then look at what (if any) configuration changes may help reduce your object descriptor usage; have you verified that LWPs are using up your object descriptors?
2 - start flipping configuration parameters on and off to see which (if any) have an effect on your object descriptor usage; keeping in mind that you will need to be monitoring your system closely so that you can a) capture metrics for your various configuration combinations and b) react quickly to any configuration combinations that degrade ASE performance
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It's not apparent from your posts how much research you've done into your situation so fwiw ... take a look at a couple blog posts that discuss statement/proc cache usage, with some details about object descriptor usage and various configuration options (including 'streamlined dynamic SQL'):
What is in my statement cache?
ASE 15.7: Prepared Statements and ASE Statement/Procedure Cache, Configuration Impact
From the 2nd blog we see this bullet which answers your question about possible disadvantages of using 'streamlined dynamic SQL' ...
"We have learned that open objects usage surges up with the streamlined option turned on, so it must be addressed in configuration in order to avoid descriptor reuse."
... so if you're seeing your object descriptor usage climbing 'too high' then you likely don't want to increase your object descriptor usage ... ?
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'course, another possible explanation for your situation is that 'number of open objects' is too low for your system ...
