Good things first - Excellent location, excellent value worth money, decent rooms with excellent views, good spa, good kid area, good pool, excellent breakfast.
What they can improve is the interior seems to be dated. Charges for wi-fi in room are ridiculous, no mini bar, average service, average house keeping.
What is bad - Don't have their own services, if you book a tour at lobby, they probably call tour operator right outside the hotel and charge you triple the price. Typically when you reserve a tour from a Hotel that is charging extra ordinary high, you expect the tour to be decent enough. What this hotel does is charge you extra high and then book you on cheapest tour available on street keeping 75% of the money in their pocket while sending you off with a seedy operator that you will never book knowingly.
So basically if you are looking for a decent place to sleep and in budget, Holiday Inn Pattaya is right choice for you. Just utilize what is covered in your rate, don't order anything extra. Don't expect anything more than that and don't expect them to provide you luxury treatment for extra orders even though you will be charged 5 star rates. Book your own tour, book your own taxi, eat on your own, drink on your own.