Add a ServiceNotApplicable attribute for cores to mark things like SaveRam and ISettable as not applicable for the given core, update the CoreFeatureAnalysis dialog to not show these interfaces for the given core (and not mark them as incomplete). Set various cores accordingly

BizHawk.Client.EmuHawk/CoreFeatureAnalysis.cs

@@ -45,7 +45,10 @@ namespace BizHawk.Client.EmuHawk
 					CoreType = core,
 					CoreAttributes = core.GetCustomAttributes(false)
 										.OfType<CoreAttributes>()
-										.Single()
+										.Single(),
+					ServicesNotApplicable = core.GetCustomAttributes(false)
+										.OfType<ServiceNotApplicable>()
+										.SingleOrDefault() ?? new ServiceNotApplicable()
 				})
 				.OrderBy(c => !c.CoreAttributes.Released)
 				.ThenBy(c => c.CoreAttributes.CoreName)
@@ -67,7 +70,7 @@ namespace BizHawk.Client.EmuHawk
 
 				bool missingImplementation = false;
 
-				foreach (var service in services)
+				foreach (var service in services.Where(s => !core.ServicesNotApplicable.NotApplicableTypes.Contains(s)))
 				{
 					bool isImplemented = false;
 					if (service.IsAssignableFrom(core.CoreType))

BizHawk.Emulation.Common/Interfaces/ICoreService.cs

@@ -1,4 +1,6 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 
 namespace BizHawk.Emulation.Common
 {
@@ -19,4 +21,21 @@ namespace BizHawk.Emulation.Common
 	{
 		public FeatureNotImplemented() { }
 	}
+
+	public class ServiceNotApplicable : Attribute
+	{
+		public ServiceNotApplicable(params Type[] types)
+		{
+			if (types != null)
+			{
+				NotApplicableTypes = types.ToList();
+			}
+			else
+			{
+				NotApplicableTypes = new List<Type>();
+			}
+		}
+
+		public IEnumerable<Type> NotApplicableTypes { get; private set; }
+	}
 }

BizHawk.Emulation.Cores/Calculator/TI83.cs

@@ -19,6 +19,7 @@ namespace BizHawk.Emulation.Cores.Calculators
 		isPorted: false,
 		isReleased: true
 		)]
+	[ServiceNotApplicable(typeof(ISaveRam))]
 	public partial class TI83 : IEmulator, IMemoryDomains, IStatable, IDebuggable, IInputPollable, ISettable<TI83.TI83Settings, object>
 	{
 		//hardware

BizHawk.Emulation.Cores/Computers/Commodore64/C64.cs

@@ -13,6 +13,7 @@ namespace BizHawk.Emulation.Cores.Computers.Commodore64
 		isPorted: false,
 		isReleased: false
 		)]
+	[ServiceNotApplicable(typeof(ISettable<,>))]
 	sealed public partial class C64 : IEmulator, IMemoryDomains, IStatable, IInputPollable
 	{
 		// internal variables

BizHawk.Emulation.Cores/Consoles/Atari/2600/Atari2600.cs

@@ -15,6 +15,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari2600
 		isPorted: false,
 		isReleased: true
 		)]
+	[ServiceNotApplicable(typeof(ISaveRam))]
 	public partial class Atari2600 : IEmulator, IMemoryDomains, IStatable, IDebuggable, IInputPollable, ISettable<Atari2600.A2600Settings, Atari2600.A2600SyncSettings>
 	{
 		private readonly GameInfo _game;

BizHawk.Emulation.Cores/Consoles/Atari/7800/Atari7800.cs

@@ -16,6 +16,7 @@ namespace BizHawk.Emulation.Cores.Atari.Atari7800
 		portedVersion: "v1.5",
 		portedUrl: "http://emu7800.sourceforge.net/"
 		)]
+	[ServiceNotApplicable(typeof(ISettable<,>))]
 	public partial class Atari7800 : IEmulator, IMemoryDomains, ISaveRam, IDebuggable, IStatable, IInputPollable
 	{
 		// TODO:

BizHawk.Emulation.Cores/Consoles/Atari/lynx/Lynx.cs

@@ -12,6 +12,7 @@ using Newtonsoft.Json;
 namespace BizHawk.Emulation.Cores.Atari.Lynx
 {
 	[CoreAttributes("Handy", "K. Wilkins", true, true, "mednafen 0-9-34-1", "http://mednafen.sourceforge.net/")]
+	[ServiceNotApplicable(typeof(ISettable<,>))]
 	public class Lynx : IEmulator, IVideoProvider, ISyncSoundProvider, IMemoryDomains, ISaveRam, IStatable, IInputPollable
 	{
 		IntPtr Core;

BizHawk.Emulation.Cores/Consoles/Coleco/ColecoVision.cs

@@ -17,6 +17,7 @@ namespace BizHawk.Emulation.Cores.ColecoVision
 		isPorted: false,
 		isReleased: true
 		)]
+	[ServiceNotApplicable(typeof(ISaveRam))]
 	public sealed partial class ColecoVision : IEmulator, IMemoryDomains, IDebuggable, IInputPollable, IStatable, ISettable<object, ColecoVision.ColecoSyncSettings>
 	{
 		// ROM

BizHawk.Emulation.Cores/Consoles/Intellivision/Intellivision.cs

@@ -13,6 +13,7 @@ namespace BizHawk.Emulation.Cores.Intellivision
 		isPorted: false,
 		isReleased: false
 		)]
+	[ServiceNotApplicable(typeof(ISaveRam))]
 	public sealed partial class Intellivision : IEmulator
 	{
 		byte[] Rom;