The upgrade is pretty safe opposed to when you switched from Poser 11 to 13. As there hasn't been any major update to Python that will render your older scripts unusable. You can also certainly continue to use the High DPI scaling override.

If everything is running perfectly for you and you're not affected by any bugs or issues though, there is no harm in sticking with what is working for you.

Below is what has been fixed so far if you are curious as to what has changed.

Poser 13.3.895 - 2024-11-14
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- Use Cache removed from SuperFly render settings to avoid memory leaks. (App) #2421
- Exporting Partial scene no longer shows file chooser twice. (App) #2424
- Implemented displacement node for SuperFly materials. (App) #2234
- Displacement renders will no longer invert shading on curved surfaces. (App) #2285
- Documentation: Poser's system requirement for the Mac is now OS 12.7.1 (Monterey or higher).  (App) #2422
- Documentation: Updated details for Default Exposure and Saturation in PostFX. (App) #1846

Poser 13.3.864 - 2024-10-14
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- SuperFly Depth of Field checkbox correctly turns off setting.  #2417 (App)
- Camera Shutter_Close parameter dial no longer breaks 3D Motion Blur in SuperFly. #2418 (App)
- Graph context value by right clicking the Parameters Palette is now correctly scaled. #2284 (App)

Poser 13.3.853 - 2024-10-04
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- Fixed memory leak affecting large scale SuperFly renders, like 2048x2048 (App) #2414

Poser 13.3.846 - 2024-09-24
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- Fixed issue with Make Movie (when Auto checked) with Japanese localization (App) #2369
- Fixed issue with Uncompress Files Python script to fail with Japanese localization (App) #2408

Poser 13.3.837 - 2024-09-15
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- Fixed issue where number of cores used for CPU renders was limited to 4 (App) #2407

Poser 13.3.824 - 2024-09-04
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- Fixed crash when trying to render SuperFly in Non-progressive mode. (App) #2393, (Beta) #484
- Fixed crash rendering HDR scenes (App) #2397
- Fixed accelerator Restore All setting so it doesn't return after removing it. (App) #2379
- Properties palette no longer scrolls out of view. (App) #2375
- Corrected mismatched naming of joints in Setup Room (App) #2391
- Corrected Poser Python DialogDirChooser docstring and pydocs parameter names (App) #2388, (Beta) #481
- Fixed issue where German or Japanese localization causes render without producing HDRI image (App) #2400
- Completed feature request - create flipped morph (App) #1813 (Beta) #211


Poser 13.3.797 - 2024-08-08
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- Overhaul of Superfly render pipeline to preserve Cycles session and use caching for faster renders #2327
- Fixed a Crash reparenting with Hierarchy Editor. #2356 (App)
- FireFly Render no longer crashes at end of render. #2380 (App)
- Queue Render not longer crashes cycling frame 1 continuously. #2381 (App)
- Added "Type-to-find" to Parameter Palette. #2345 (App)
- Fixed Parameters search box overlapping rename field in Properties tab. #2376 (App)
- Added preference to not collapse all hierarchy displays or remember collapsed state. #2082 (App)
- PostFX on some Firefly renders no longer washed out. #664 App)
- Added a scrolling to PostFX dials panel. #1590 (App)
- "Target geometry has wrong number of vertices" dialog box no longer stuck in infinite loop. #2351 (App), #479 (Beta)
- Added ability to reintegrate a denoise channel back into the render process. #1975 (App)
- Added Save for Sharing back to localized German & Japanese versions. #2344 (App)
- Added Collada|RWY exporter back to the Mac version. #2300 (App)
- Improved Joint center to eliminate getting into a confused state. #2318 (App)
- Poser no longer freezes if wrong PMD is loaded. #2203 (App)
- Improved the use of the Gradient Bumps in the Material Room. #2341 (App)
- Unimesh figures in group now correctly respond to group visibility setting. #2181 (App)
- Cleaned up the UI on the Materials Apply tab. #544 (App)
- Fixed a crash in Cg preview gl shader scripts causing memory leaks. #2385 (App)
- Increased Joint zones list in Joint Editor item selection events from 50 to 500. #2340 (App)
- Fixed the Environment Texture shader node to correctly load map from Python SetString(). #1811 (App), #217 (Beta)
- Added new Python ImageType object which supports loading any image file from disk and creating wx.Image/wx.Bitmap. #1799 (App), #214 (Beta)
- Added ability for Poser Python command to get and set light intensity. #2387 (App)

Poser 13.3.686 - 2024-03-13
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- Fixed issue with Background Renders failing

Poser 13.3.680 - 2024-03-08
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- Talk Designer: Transcript correctly clears out previous supplemental text when loading a text file. #2323 (App), #472 (Beta)
- Talk Designer: Updated default Viseme mappings so all Cartoon Characters work. #2328 (App), #473 (Beta)
- Parameters Dials: Locked the min max and disabled the controls for geometry dials. #2320 (App), #469 (Beta)
- Added Denoise to the Raytrace Preview when set to SuperFly render. #2123 (App), #470 (Beta)

Poser 13.3.669 - 2024-02-29
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- Fixed issue with Vicky 4 pmd not injecting external morphs. #2309 (App)
- On the Mac: fixed Crash when renaming a figure from the hierarchy panel. #2294 (App)
- Replaced current Lip Sync tech with Rhubarb Lip Sync. #2308 (App)
- Fixed 'Install from Zip Archive' to be case insensitive on .ZIP suffix. #2311 (App)
- Scenes sent to Render Queue correctly recognize the adaptive sampling setting. #2297 (App)
- Scenes with HSV node no longer ignored in Render Queue and Render in Background. #2292 (App)
- Normal maps correctly rendering when using PoserSurface root. #2276 (App)
- Replacing figures or props now gives warning message saving to the library when file compression/uncompression doesn't match. #2301 (App)
- Corrected Simple Color node so that it no longer creates invalid results in the cg shader code. #2286  (App)
- Corrected Joint center going into a confused state in the Joint Editor. #2318 (App)

Poser scripts by Snarlygribbly