If you want a Holographic style optic, I have a SOTAC branded XPS3 from Ebay and it works a treat. Bright enough for use outdoors on a sunny day but doesn't have huge issues with parallax in my experience but it does exist, it always will with cheap airsoft optics. They're pushing the top end of 'budget' in airsoft but it's worth it.
Between that and my HolyWarrior S1 XPS3 I struggle to choose which is better. The HW S1 has an annoying habbit of not turning on/not accepting CR123A batteries, i've spent 20+ min finger fucking it before it works where the SOTAC one just turns on instantly, zero issues. The HW however has light levels low enough to be used with NVGs (for the ultra larpers that use them which rules out 99% of players) The SOTAC can be green or red reticule, whichever you prefer.
There's an ebay store called "mk1_tactical" who sells a lot of SOTAC branded gear. You'd likely benefit from their
Comp M2 offering. A mistake people often mistake is buying an optic that is too low (due to face protection) meaning they have to bend their neck into a strange place to get a good sight picture. After realising their mistake they buy a riser. The Comp M2 i've linked earlier comes with the riser/mount meaning you're unlikely to have this issue.